Gold Occurrences in Southern Queensland

Pikedale (32km north-west of Stanthorpe). This field is on the south-eastern extremity of the “gold belt” which extends from Leyburn in the north to Pikedale in the south. Gold production was confined to reef mining. Records show that the auriferous reefs were small but fairly rich. They were worked by small parties, and were generally abandoned about the 30m level.

Mineralization was found in both quartz ‘dykes’ and fissure fillings, strongly faulted in part, and usually carrying pyrite. Occasionally cassiterite (tin) was found associated with the gold in some of the mines. The reefs were not very large or very rich and difficulty was encountered with recovery of gold associated with pyrite. No full record of actual production has been found. The country rocks are slate, indurated shale, and greywacke striking north and dipping at high angles. Small dioritic lenses have been found along relict bedding planes of the sediments in some of the mines. Strike of the auriferous deposits varies from east to east-north-east and they have a variable dip.

No general statements can be made regarding future prospects of these mines as the factors leading to their closure are unknown.

Waroo Gold and Copper Mine

The Waroo Gold and Copper mine is situated on portion 5, Parish of Waroo, 67km by road west of Stanthorpe and 28.8km east of Cobba-da-mana railway siding. The lode was discovered in 1906 and the mine worked spasmodically till 1913. Mineralization was exploited to a depth of 61m and for a strike length of approximately 90m. Some 2,000 tons of ore was treated on the site either by smelting or by cyanidation for an average yield of 113 oz of gold per ton.

The mineralization occurs in a series of easterly trending indurated shales, and inter-bedded fine-grained quartzites, with steep southerly dip. The lode varies in width, from a few inches to 1.2m and appears to be conformable with the strike of the metasediments although it cannot be considered to be inter-bedded with the country rock. Gold values were erratic. Copper mineralization was associated with the gold, but appeared to be uneconomic on its own. In 1931 the mine was reopened for inspection and testing, but activity was short-lived; the gold content of the ore proved to be sub-economic at that time.

Near Warroo, 32km further west, another gold-bearing lode was exploited to a reported depth of 60m until local smelting became unpayable.

Texas (85km by road west of Stanthorpe). The old Silver Spur Mine, 11km east of Texas, produced considerable amounts of silver, lead, gold and copper, the zinc contents remaining in the slag dumps. Existing workings, to 152.5m depth, offer possibilities for further prospecting, but unwatering and reconditioning would be necessary. In recent years interest has been displayed periodically by various mining organizations.

WARWICK AREA - Overview

Gold was first discovered at Lord John’s Swamp (Lucky Valley Goldfield) being 19km south-east of present day Warwick in 1852 whilst in 1863 rich but limited alluvial gold was uncovered on Canal Creek was an alluvial goldfield only (45km south-west).

The following goldfields are based around Warwick (161km by road south-west from Brisbane). Following close on the Canal Creek discovery were further finds at Talgai (Named: Darkie’s Flat from 1863 to 1864, 34km west-south-west), Thane’s Creek (39km west) in 1869, Pikedale in 1877, Leyburn (45km north-west) in 1872, and Palgrave (34km south-west) in 1877.

Both alluvial gold and reef gold were won from Talgai. Thane’s Creek was primarily an area of reef mining; at Pikedale and Leyburn little or no alluvial gold was won. Little is known of the Palgrave field. The period of principal production was prior to 1905. Attempts at revival of reef mining in the 1930’s were only moderately successful, and did not survive for long. Any future prospects appear to lie in further development or known reefs below the old shallow workings.

In the primary deposits, payable gold values occur in narrow shoots in small fissure veins which could not at the time of working be profitably followed much below 30m. Where there is reason to believe that the shoots were not worked out further prospecting in depth might be justified.

Lucky Valley Goldfield

No returns for alluvial gold from this field have been recorded. The gold was won from alluvium in the “valley” and the gullies running into it. At the head of the “valley’’ a small hill of metasediments carried leaders of quartz showing free gold. A shaft was sunk on these leaders but was abandoned after 9 tons or ore, yielding 12 oz 6 dwt of gold, was recovered. Small quartz reefs have been prospected for gold near Omoral railway siding.

Canal Creek Goldfield

Gold was discovered by a party of seven Frenchmen working a gully 4 miles due north of the old Canal Creek Station. On the eastern side of Canal Creek “excellent” alluvial ground was worked up to the base of the divide, but nothing of any consequence has been discovered on the western side of the creek. The depth of alluvium was reported as ranging from 1.5 to 3.6m, bottoming on pipe clay. The thickness of the wash varied considerably and it tended to occur as lenses. Archibald estimated that between 1863 and 1887, approximately 20,000 oz of gold had been recovered. Although leaders of auriferous quartz were found along the divide in metasediments on the eastern extremity of the alluvial deposits, there is no record of any attempts to work these finds.

Talgai Goldfield

The Talgai Goldfield, originally known as Darkie’s Flat, has supported both alluvial and reef mining with spasmodic workings till recent times. The workings were confined to limited gully-raking and occasional attempts at reef mining. The richest alluvial gold was won from Dun’s (Dunn's) Gully and the head of Gum Flat, 4.8km south of the township of Pratten. The alluvium was rich but patchy and ranged in depth from 60cm to 6m. The gold was coarse and many nuggets ranging from 1 to 16 oz were unearthed. The largest nugget recorded from the alluvial fields of the Warwick area came from this vicinity. The nugget weighed 55 oz and was found by Mr. H. Gibson in 1895.

Traces of tin were commonly associated with the alluvial gold found on the field, particularly in Dun’s (Dunn's) Gully and the gullies leading on to Gum Flat; but nowhere was the mineral recorded in commercial quantity. Little trace of it is seen in the country rocks. Many reefs have been worked on the Talgai field with varying results. Gold occurrence appeared to be patchy. Some early phenomenally rich crushings were reported, and stone treated commonly averaged around 1 oz per ton.

However the small average size of the reefs, faulting, and/or shortness of the shoots were inimical to economic development in depth. Robert Logan Jack (Government Geologist) recorded that the Queensland reef was believed to be the first gold reef to be worked in Queensland . At a depth of 21.3m, 600 oz of gold was recovered from 4 tons of ore. The main ore shoot was lost at depth when intersected by a quartz reef carrying pyrite. The deposits on the field vary from thin stringers to veins 6 feet across, usually of quartz, within the metamorphics. General strike of the reefs is west to north-north-west, with southerly dip. The largest reefs found on the field have been worked along the spur of Mount Gammie North.

Thanes Creek Goldfield

Although Thane’s Creek Goldfield is not contiguous to Canal Creek, it appears to form an extension of the same belt of auriferous country. In contrast to the workings along Canal Creek, no alluvial gold of any consequence has been found, most of the gold won being derived from reef mining. Lack of suitable crushing and treatment facilities, erratic gold values and faulting of the ore shoots appear to have been the main reasons for the decline of the field. No mine has been developed below about 36m the average depth being about 18m.

Leyburn Goldfield

No returns of production are available. The gold is found in dark laminated quartz reefs which tend to form lenses parallel to the general strike of the country rock and pitching at varying angles to the south-east. Gold has shown erratic distribution within the ore shoots; the average value of stone treated rarely exceeded 1 oz per ton. The country rocks are predominantly pink and purple phyllites, slates, and quartzites, which strike approximately N. 130º E. and have vertical dip.

Palgrave Goldfield

Little is known of the history of the workings of this field. The country rocks are predominantly greywacke and slate striking a few degrees west of north and dipping to the west. Personal communications with old miners who know the field suggest that the ore was of low grade and the mines small. Failure of the mines of all the goldfields appears to have been caused by the low average grade of the ore, patchy values, faulting, primitive methods of mining and inadequate equipment, lack of suitable crushing and treatment plants, inability to treat the pyritic ore, and high cartage cost.

Proclaimed Goldfield Areas (acres)

Lucky Valley 1851 = 16,000 acres; Talgai 1863 = 49,220 acres; Canal Creek 1863 = 13,960 acres; Thane’s Creek 1869 = 11,000 acres; Pikedale 1877 = 19,200 acres; Leyburn 1872 = 4,780 acres; Palgrave 1897 = 3,226 acres.

More information to be added

BRISBANE AREA

Gold is associated with quartz reefs of the Neranleigh-Fernvale Beds and Bunya Phyllite. Minor gold occurrences were reported in the Brisbane city area and environs by Ball, and near Pimpama Creek. Robert Logan Jack, Morton, Ball, and Knight described gold from quartz reefs in the Brookfield-Enoggera area, while Reid reported a minor occurrence of gold and arsenopyrite from the headwaters of Banks Creek. Production from the Eclipse, Surprise, Double D, and Mount Aurum Mines at m.r.s 606588, 605596, 605593, 603596 (Ipswich Geological Sheet) was 4kg of fine gold.

At Camp Mountain (16 km west of Brisbane) near Samford, the Camp Mountain mine and the Golden Spur mine were investigated by Ball, Connah, and Morton. Gold values from the cellular quartz at the Mountain Camp mines were less than 3 grams/tonne, whereas those at Camp Mountain mine exceeded 7 grams/tonne.

Gold occurs in three different environments:

(a) Associated with quartz reefs in the Neranleigh-Fernvale Beds, Bunya Phyllite, and Maronghi Creek Beds;

(b) At contact zones between granitic rocks and Palaeozoic basement;

These are derived by erosion of small lodes in the Palaeozoic Neranleigh-Fernvale Beds and Bunya Phyllite. The most important mine in the Sheet areas was the Mount Taylor Gold mine at Kingston (m.r. 627567 Brisbane Sheet) 24km south of Brisbane. Jack described the workings and the production for the period July to November 1898, while Benjamin Dunstan described gold occurrences near Kingston, and indicated there was a large low grade gold deposit in the area. This deposit was worked from 1932 to 1950 by Kingston (Open Cut) Gold Mines Ltd. The mine was abandoned in 1954 because the recovered grade was too low for profitable operation.

Production from 1932 to 1954 was 149,497 tonnes of ore, which yielded 612,303kg gold at an average grade of 4.1 grams/tonne. The ore occurs in altered argillite of the Neranleigh-Fernvale Beds. which dip 12º to the south-west. The host rock has been sericitised and replaced by silica. Subsequent fracturing gave criss-crossing white and colourless quartz veins averaging 12mm wide, which contain native gold and limonite. The extent of the ore body was 183 by 122 by 17m. Hall and Carter described the results of testing of the grade of the mine area, while calculations of reserves by Blanchard were 355,755 tonnes of grade 5.4 grams/tonne gold under 250 000 tonnes of overburden. Access to this area is now out of the question as it has now been built on.

Other gold occurrences

Gold occurrences near Ormeau (48km south of Brisbane), do not offer much inducement for further prospecting.

A prospect near Beenleigh (m.r. 636559 Brisbane Sheet) contains values of 4.6 to 7.7 grams/tonne in a quartz vein in the Neranleigh-Fernvale Beds.

Gold occurrences at the contacts of Palaeozoic rocks and later intrusions are reported from Mount Coot-tha (m.r. 612587 Ipswich Sheet, Milford Rocks (m.r. 527643 Ipswich Sheet), Nukinenda (m.r. 526644 Ipswich Sheet), and Alice Creek (near m.r. 526593 Ipswich Sheet). At the Mount Coot-tha mine, (near the present day Channel 9 Television Studios) gold averaging 11.3 and 7.3 grams/tonne was produced from 0.4 tonnes of ore in 1940. The mineralisation is in foliated Bunya Phyllite at the contact with the Enoggera Granite. Native gold is associated with arsenopyrite, chalcopyrite, and pyrite in irregular pyritic quartz veins and segregations.

Ravensbourne (Near Toowoomba)

Gold grades generally less than 3 grams/tonne were reported by Ridgway from several small prospects in the vicinity of Bunkers Hill, Ravensbourne. These occurrences are associated with a brecciated quartz-kaolinitic vein in the Permian Cressbrook Creek Group.

NANANGO AREA

Nanango Goldfield

The Nanango Goldfield 2km east of Nanango (209km by road north-west of Brisbane was first worked in the 1880’s. Two batteries were erected but the returns from crushings were unsatisfactory. The Gray’s Luck gold mine was sunk to 85m without finding gold in payable amounts. A shaft was sunk about 2km north-east of Nanango in 1935 but because of low values and water problems there was little or no production. The gold is very fine and associated in places with galena or pyrite. No records of production during the early productive years of the field are available. The country rocks are grey and black shale and siltstone intruded by a felsite dyke varying between 0.3 and 6m in width and dipping westwards at 45°. Most of the gold was found to be restricted to groups of discontinuous quartz veins in the dyke. They are flat-lying and seldom more than 300mm wide.

On the Golden Gull prospect near Mount Powers, 10km east of Nanango, a decomposed dyke cutting steeply dipping slate and quartzite is cross-veined over a width of 5m by quartz.

Scrub Paddock Diggings

The Scrub Paddock Diggings (32km north-east) were worked at an early stage in the State’s history. The last period of marked activity included an attempt by an English company to work a group of auriferous copper veins at Scrub Paddock. Despite intermittent prospecting over the wide area available, no discoveries of note have since been made. In the 1860’s and 1880’s gold was mined from Moonarrumbia Creek and German’s Gully on what was known as the Scrub Paddock diggings, 32km north-east of Nanango. Rands reported that nuggets as large as 400grams were found. Gold was also produced from the Gooroomjan Creek copper mines in the same area.

Seven Mile Diggings

The Seven Mile Diggings are situated near the junction of Yarraman and Cooyar Creeks, about 11km south-east of Nanango. Alluvial gold was worked in the 1890’s and up to 700 men were working there at one time. However, no large scale mining of reefs or alluvium was carried out Morton reported on attempts to revive alluvial mining but the ground was apparently neither extensive nor very rich. The greater part of the alluvial deposits was derived from insignificant veins in granite.

Milford Rocks

At Milford Rocks, schist and quartzite of the Maronghi Creek Beds are intruded by dykes and tongues of Eskdale Granodiorite. Gold is found in small veins in the granite and altered metasediments near the contact. The Nukinenda Gold mine is at the contact of a diorite dyke and quartzite, slates, and cherts of the Maronghi Creek Beds. No vein section of ore greater than 0.9m wide was observed, and although gold values up to 23 grams/tonne are locally present, discontinuity of economic grade ore precludes profitable exploitation.

Workings at Alice Creek were situated at the contact of porphyritic dykes and metamorphosed mudstone of the Cressbrook Creek Group at m.r. 526593. The gold, which assayed up to 37 grams/tonne to a depth of 11m in the main shaft, occurs in a quartz vein (averaging 30mm wide) in a porphyrite dyke.

Taromeo Creek

In the Taromeo Creek area about 10km north-north-east of Blackbutt, several shafts were sunk on the Black Diamond, Red Queen, and Lady Mary prospects. Ball reported that copper and silver occur with gold in reefs in granite. At the Golden Bird prospect, 5km north of Blackbutt, gold occurs in quartz reefs, irregular veins and a chloritic lode which showed traces of cobalt. Gold values rapidly became impoverished with depth. Gold occurs with bismuth and silver-lead in the Mount Langan area. Ball reported on the discovery of gold at Nukinenda, 10km south-south-east of Blackbutt. The veins exposed were very small but rich.

Blackbutt area

Prospecting of small auriferous reefs and leaders has been carried out near Emu and Possum Creeks in the Blackbutt area without marked success.

Benarkin area

At the head of Oppossum Creek, about 11km south-south-west of Benarkin, gold occurs in two distinct reef systems in fine-grained hornblende diorite. A.K. Denmead considered that reserves of payable ore were small. About 6km north-north-east of Yarraman, gold occurs at the base of Tertiary sediments capping Permo-Triassic granodiorite. A.K. Denmead regarded the grade and thickness of the wash as too low to be worked profitably.

Manumbar area

The Golden Spur mine is at the head of Mortimer Creek in the Manumbar area, north-east of Nanango. Morton described the deposit as a fissure type, the walls being parallel to the schistosity of the enclosing schists. Above the water table the reef which averages 300mm in width is composed of iron gossan, quartz and some pyrite. Assays gave about 15 grams/tonne gold.

Monsildale

At the Hollyborne mine, about 2km west of Monsildale homestead, Cameron described the reef as consisting of fairly heavily mineralised quartz carrying pyrite and gold. It strikes at 035° and dips nearly vertically between walls of diorite. Assays gave up to 400 grams/tonne gold. Gold also occurs in the silver-lead mines of the Monsildale area. Alluvial gold was worked on Squirrel Creek about 11km north-west of Monsildale.

SUNSHINE COAST AREA

North Arm gold deposits

North Arm (117km by rail north of Brisbane). These deposits are about 2km north-east of North Arm township. The discovery of auriferous quartz reefs in a hitherto unproductive series of volcanic rocks was made in 1929. Gold mining commenced in 1930, but the occurrence of fine gold in gullies in the area had long been known.

Initial crushings from the Golden Surprise yielded 12.6kg of bullion from 51 tonnes of ore and gave impetus to further mining. In 1932 the Golden Surprise produced 1,722 tonnes of ore yielding 83.5kg of bullion. By the end of 1937 when mining ceased, total production amounted to 845.9kg of bullion from 12,050 tonnes of ore and 12,212 tonnes of sands. Efforts were made to locate workable auriferous deposits further afield but resulted in failure.

The Quincey and Corvi mine produced 213.2kg of bullion. Other mines included the Golden Surprise Extended, Golden Wonder, Golden Dawn, Hidden Treasure and North Arm Co. Their combined production was only 13.9kg. The country rocks consist of volcanics of the North Arm Volcanics. Well defined reefs of hard white quartz occur in a system of roughly parallel fissures striking north-west. With the exception of the Coolum reef which dips 60º south-west; the reefs are vertical. They are generally free from sulphide except where appreciable gold values occur. The ore contained dark bands of finely disseminated naumannite (silver selenide), together with specks of gold and some cerargyrite. Morton tentatively concluded that mineralisation was related to the intrusion of rhyolite dykes during the final stages of volcanicity.

It is of interest to record that the free gold was so highly alloyed with silver that it looked almost white in colour and is associated with the rare mineral naumannite (silver selenide).

Jimna Goldfield

Yabba Goldfield (32km north of Kilcoy); also known as the Jimna Gold Field is 10km east-south-east of Jimna. It was essentially an alluvial field, and is credited with rich returns in the early years from deposits on Jimna and Sandy Creeks. Reef-mining followed on a small scale for some years with two plants on the field. A few small reefs carrying fair values have been worked in recent years.

Alluvial gold was first worked from Jimna and Sunday Creeks in the 1860’s and later was obtained from terraces adjacent to these streams. Workings extended approximately 6km westwards from the headwaters of Jimna Creek. With the gradual exhaustion of alluvial gold, reef mining contributed more prominently to the output of the field. Mortimer’s reef was first worked in 1869. The Empress is possibly an extension of Mortimer’s reef and consists of quartz with massive pyrite and minor galena associated with the gold. Production between 1897 and 1900 is recorded as 432 tonnes of ore yielding 13.1kg of gold.

Reef mining was originally recorded in the Mount Rollman area in 1893 and some further activity was reported by Ball. In the 1930’s, sporadic mining, both from alluvial and reef workings, was resumed. The Sultana United claim, located south of the old Jimna township, produced a total of 68 tonnes of ore yielding 2.8kg gold between 1940 and 1948. Only very minor activity has been carried out in the area since then.

At Yabba, metasedimentary rocks consisting of slate, phyllite, chert, and arenite have been intruded by granite and contain narrow quartz veins, some of which carry gold. Alluvial deposits marginal to Jimna Creek carry erratic gold values. Reefs occur both in metasediments and in granite although most attention has been concentrated on the latter. Most reefs strike east with the exception of the Empress reef which has a north-north-east strike. In general, reefs are narrow and low grade and the very hard grade host rock made mining costly.

Other local gold occurrences

The Barlows Freehold gold mine is about 2km east of Woondum. The main workings are on a reef 150mm wide and dipping 60° west-south-west. East dipping shale of the Triassic Kin Kin Beds forms the country rock. At a two-head battery operated in the mid-1890’s, 74 tonnes of ore were crushed for a return of 0.9kg of gold. Between 1895 and 1906, tributers won 105 tonnes of ore.

The Mount Wonga mine, 1.6m west of Woondum, was originally worked between 1892 and 1894 when 395 tonnes of ore were treated for 6.5kg gold. Two shafts were sunk, each to a depth of 92m. The country rocks consist of indurated shale, conglomerate and sandstone of the Triassic Keefton Formation. According to the Government Geologist, Benjamin Dunstan, the gold occurred where the abundant reefs cut andesite dykes.

Gold was discovered in the Kin Kin area in 1918, but the deposits proved to be unpayable. A gold deposit 6km west of Traveston was prospected in 1885 and 1892. Although initial samples assayed about 70 grams/tonne, trial crushings returned only 18 grams/tonne gold and the claims were abandoned.

The Borgam workings are on Yabba Creek about 20km west-south-west of Imbil. The reefs were worked in the 1930’s. They were somewhat small but values on two were sufficiently high for profitable treatment (24 tonnes crushed for a little under 92grams/tonne gold). The country rocks consist of phyllite and micaceous schist striking north-west and dipping south-west. In the vicinity of the Yours and Mine mine and the McAuliffe’s mine, the schists are intruded by diorite. The quartz reefs occur near the diorite contact. Brooks described the Sandy Creek prospect being 3km south of the main Borgam workings. Auriferous quartz reefs also carry arsenopyrite and sphalerite with minor chalcopyrite and galena.

Wieland’s mine is 5km south-south-west of Imbil near Caseys Gully. Gold was mined from a small flatly-dipping quartz vein in hornblende porphyrite intruding metasediments. The vein contained small rich patches but pinched out at a shallow depth. Recorded production is 0.2kg retorted gold from 2 tonnes of ore. Alluvial gold was worked on Breakneck Creek, 5km south of Imbil, and narrow reefs in granodiorite were prospected. Between 1928 and 1933, 6.0kg of bullion was extracted from 124 tonnes of ore. Browns Gully, about 2km south-south-east of Imbil, was worked for alluvial gold, and a few flat “leaders” in granodiorite were also prospected.

The O’Doherty mine, 5km by road south-south-west of Kenilworth , never yielded gold in payable quantities. Production from 1930 to 1934 was 0.7kg gold from 30 tonnes of ore. On the divide between Walli and Chinaman Creeks, about 5km south of Kenilworth, gold occurs in a quartz-calcite reef in fine grained, highly altered, basic volcanics intruded by granitic rocks. The ore shoot had a length of approximately 27m. Individual crushings gave recoveries between 46 and 61 grams/tonne gold. Several gold prospects occur about 9km south of Kenilworth in State Forest Reserve 736. At Sawtell’s prospect, gold occurs in association with bismuth carbonate and pyrite in a fissure formation. The country rock is fine to medium grained hornblende diorite. Morton reported a small shoot of payable ore, but no production was recorded.

At the Snake Creek prospect, about 2km west of Sawtell’s, four flat reefs in granite assayed slightly less than 31grams/ tonne gold. They were not large enough to be payable. Government Geologist, A.K. Denmead described auriferous, arsenical quartz veins in greisenised granite on Chinaman’s Creek about 3km downstream from Sawtell’s prospect. Values up to 107 grams/tonne were recorded. In the Kidaman Creek area, 8km south-east of Kenilworth , some slightly mineralised veins were prospected, but no payable gold was found. Alluvial gold was worked on Walli and Chinaman Creeks in the early 1900’s. Booloumba, Peter and Bundaroo Creeks, several kilometres east of the Yabba goldfield, were worked for alluvial gold although the effort necessary to locate the small rich pockets generally proved unrewarding. The alluvial flats are small in size and number owing to the steep gradient of the streams. Reef deposits were worked with some success but production figures are not available. The rocks of the area include green slate, phyllite, chloritic schist and quartzite traversed by numerous barren quartz reefs. Auriferous quartz veins occur in a granitic intrusion at the head of Peter Creek alloyed with silver that it is almost white in colour and is associated with the rare mineral naumannite (selenide of silver).

GYMPIE AREA - Overview

Gympie (170km by rail north of Brisbane). The highly auriferous reefing area at Gympie was confined to a heavily faulted strip about 3km long by 1km wide This small area has been responsible for a large proportion of the field’s production. Operations were ultimately continued to depths of considerably over 600m on the Monkland end of the field. The mines of the main belt form an extensive connected group, now filled with water. Owing to the prohibitive expense involved in dewatering and reconditioning these mines, it is doubtful whether any of the connected group of workings can be deemed worthy of further consideration. Since the decline of major mining operations - about 1917, numerous attempts have been made to exploit blocks of shallow ground. Relatively few of these attempts have met with success. For many years production was maintained by cyanidation of old tailings, but this has now ceased.

In terms of production, gold has been the most important metal mined in the Gympie Geological Sheet area. The Gympie goldfield during its productive period was one of the three major goldfields in Queensland. The other four proclaimed fields in the Gympie Geological Sheet area are the Glastonbury, Nanango, Yabba and Kilkivan fields. Gold was also worked at North Arm (South of Gympie) and numerous small occurrences are known elsewhere in the Gympie Geological Sheet area.

Gympie Goldfield

The Gympie Goldfield covers an area of 310 square kilometres although the most productive section of the field occupies a belt north of the Mary River within the town area of Gympie, about 6km long and 2km wide. The most comprehensive geological reports on the Gympie goldfield during its productive period are by Rands . The Government Geologist at the time, Benjamin Dunstan, mapped the goldfield in detail and the results were published in a 36 map atlas. Summary descriptions of the field were prepared by Morton and the Department of Mines. This description of the Gympie goldfield is largely extracted from the latter report.

Rich alluvial gold was discovered by James Nash in September 1867, and production from reefs began the following year. In 1872, deeper sinking by syndicates demonstrated that ore shoots recurred at lower levels with intermediate barren sections. In the Monkland (southern) end of the goldfield, mining was carried out to depths exceeding 762m.

The West of Scotland shaft reached 964m. Exhaustion of the deposits accompanied by drainage problems caused work in the deep ground to cease in 1925. Since then mining operations have been confined to relatively shallow prospecting and the cyanidation of large accumulations of tailings. Attempts were also made on several occasions to exploit the deep alluvial ground on the Mary River, but with little success.

A neglected portion of the field known as the Great Northern Block referred to by Ball and Reid was tested with disappointing results in the late 1930’s. It had previously been worked only in the Great Northern mine between 1903 and 1917 yielding 120kg of bullion. A few small mines were worked south of the river in the Dawn area. The largest was the Dawn mine which operated from 1869 to 1884 and from 1902 to 1911, the total production for the latter period being approximately 429.3kg gold bullion. The area was prospected without success in the 1930's.

In the 1890's and early 1900's some gold mining was carried out in the Veteran area 12km north of Gympie. Gold occurred in a reef where it intersected highly altered dykes. An unsuccessful attempt to work the reef was made in the 1930's.

Since 1967, a resurgence of interest in the Gympie goldfield has been shown by the sinking of two shafts and several drill holes. To date there have been no significant results. The country rocks of the Gympie goldfield consist of Permian marine sediments and volcanics of the Gympie Group. The rocks generally strike north-north-west and dip 20° to 22° east with great uniformity although in some areas (e.g. the Great Northern Block), they are disturbed by faulting.

The gold deposits are a classic example of the influence of wall rock composition on ore deposition. The major control of mineralisation was the intersection of quartz/calcite veins with beds of pyritic carbonaceous shale (‘slates’) containing graphitic ‘floors’ within them or ‘breaks’ immediately above or below them. Flat-pitching ore-shoots occurred in the reefs only where they crossed the carbonaceous beds. The one exception was the New Dawn mine to the south of the river where volcanics formed the country rocks of the auriferous shoots. In the Inglewood dyke, which was gold bearing, where replaced by quartz, the shoots closely followed the contact of the dyke with slate.

The favourable beds lie towards the base of the Gympie Group. They occupy four horizons in the Rammutt Formation, a 600m thick sequence of alternating sediments, pyroclastics and some lavas. The most productive ‘slate’ bed in the Rammutt Formation was the uppermost one (the ‘Phoenix or Monkland Slates’). These are approximately 60m thick and are immediately overlain by massive volcanic conglomerate and arenite. The “slates” consist of alternating thick-bedded shale and arenite all of which are carbonaceous.

The next two productive horizons below the 'Monkland Slates' occur at intervals of 40m and 23m, respectively, and are shale beds 4 to 5m thick. At 183m below these, a few hundred metres of greywacke with lenticular beds of massive shale form the fourth productive horizon. With few exceptions, the strike of the numerous, parallel, fissure-filling reefs is the same as the country rocks, i.e. north-north-west; but they dip at 60° to 80° west. Many occupy faults and some are, in part, associated with andesite dykes. The reefs generally consist of one or two veins occupying the hanging wall and footwall of the fissure with veinlets occurring between them. The fissure filling is brecciated country rock, chlorite, and calcite, and the veins are of quartz or quartz and calcite. In favourable horizons, the whole of the fissure filling was auriferous. The richest concentrations occurred where dip faults intersected the veins.

Faulting is of several ages and is usually normal. Numerous, more or less parallel, east striking dip faults (cross-courses) some of which have throws of a few hundred metres, are younger than strike faults which in turn are younger than bedding plane faults All three sets are younger than the reefs which themselves occupy strike faults. A few dykes also occur in faults in the country rocks. Of these the most notable is the Inglewood dyke which marks the virtual southern limit of the field because of the magnitude of the downthrow on the southern side.

The Permo-Triassic sequence in the Gympie area was probably folded in the Early Triassic with an unconformity at the base of the Keefton Formation representing earth movements at the end of Permian sedimentation. Faults including those occupied by the reefs are tensional and probably post-date the folding. If this is so then the gold was probably introduced in the Middle Triassic. The nearest granitic intrusion to the Gympie reefs is the Woondum Granite. about 5km to the south-east. It is Middle Triassic in age i.e. Phase II of the Gympie Epoch. Almost all of the gold was in the free state although in some places small amounts of pyrite, galena, sphalerite, chalcopyrite and, locally hessite were associated with the gold. ‘Specimen gold’ occurred commonly in extremely rich patches. The richest reefs were the Glanmire, Great Eastern, Columbia, Glasgow, Inglewood, Monkland, New Zealand, Orient, Oriental, Phoenix, Scottish, Smithfield and Victory.

Total recorded production to the end of 1971 is given officially as 106,639kg. This total includes small returns from the Glastonbury, Kilkivan, Yabba and North Arm goldfields. Since 1870, some 4,572,225 tonnes of ore were crushed for a return of 116,638kg of gold bullion. This figure does not include alluvial gold or the returns from cyanidation of tailings. It is estimated that the amount of silver produced from the bullion was probably of the order 16,000kg.

In the Two Mile area, the Golden Crown was the most productive mine, yielding 1,316.8kg bullion from 44,672 tonnes of ore. Treatment of the Gympie ores was simple and involved battery crushing and amalgamation. Parcels of pyritic concentrates were only occasionally sent to smelters. Cyanidation was practised on a small scale until 1925, when deep mining ceased. Treatment of the huge accumulations of tailings, which continued until 1955, then became the main source of production.

At the Great Gorge mine, about 13km north-west of Gympie near Curra, a quartz reef 300 to 600mm in width carried between 16 and 31 grams/tonne gold. The reef is in slate, shale and quartzite of the Rammutt Formation. Production for 1900-1901 totalled 343 tonnes of ore crushed for 3.4kg gold.

To be continued

Glastonbury Goldfield

Glastonbury (13km west of Gympie). Gold was discovered in the Glastonbury area in 1885. Until 1888 the bulk of the production came from alluvial workings along Stone Water Creek, after which reef mining became dominant. Early mining was concentrated on the area south of the creek. The King reef was worked in the periods 1917-1920 and 1932-1949. Some further underground exploration and minor stoping was carried out on the Divine King reef, and the Pioneer reef in the 1960's.

The highest recorded production for a single year was in 1889 when 20.2kg of bullion was produced from 551 tonnes of ore, in addition to 2.3kg from alluvial mining. Some 18.1kg of gold was extracted from 485 tonnes of ore in 1916. In the last productive period, 1935 to 1950, a total of 541 tonnes of ore yielding 16.3kg of gold were mined from the southern section of the King reef.

Gold-bearing quartz reefs occupying fissures occur in altered sedimentary rocks near a granite contact. They vary in thickness from a few cm to about 1m. Host rocks for the mineralisation are light brown shale and dark grey indurated quartzite dipping south at a low angle and intruded by granodiorite. Gold-bearing quartz reefs occur in both the sediments and granitic rocks of the area. The King reef strikes north to north-west and dips 30° to 40° south-west. Most reefs in the area have a similar attitude. They consist of iron-stained quartz carrying free gold with minor sulphides, principally galena and sphalerite. The reefs are up to 300mm wide in places but break up into veins 50mm to 75mm wide. The reef in the Black shaft of the Divine King mine is fault controlled.

The output from the field has not been large. Small-scale operations were formerly conducted by a company which operated a small battery and concentrating plant.

KILKIVAN AREA - Overview

Kilkivan (48km by road west of Gympie). On this old goldfield, restricted but rich shallow alluvial deposits were worked and reefing followed. There has been little gold production for about sixty years, but a few men have been engaged near the town and on the Gold Top provisional field, 8km distant. Copper deposits were worked to a small extent at an early period at Mount Coora, Mount Clara and Black Snake. Re-opening of an old cupriferous gold lode at Black Snake in 1939 resulted in productive operations, with crushing, tabling, flotation and cyanidation plant on the ground, till 1949. Recently, several deposits in the area have been the subject of Departmental investigation by drilling.

Kilkivan Goldfield

The main groups of deposits are near Kilkivan, on the Black Snake plateau, at Gold Top, and near Tansey. Most production appears to have come from the Rise and Shine reef, 1km east of Kilkivan. A narrow mineralised zone 500m long has been prospected by numerous shafts, pits, and costeans. The country rocks are undifferentiated Palaeozoic greenstone with minor phyllite, chert, and shale, and are cut by andesite dykes which may be related to mineralisation. The arcuate reef strikes from north-west to north and dips steeply. Production was mainly from the oxidised zone to a depth of 20m, where free gold occurred in a quartz-calcite gangue. Below this, primary sulphides are associated with quartz and calcite veining in sheared, brecciated greenstone. Total recorded production is 122.1kg gold, of which 85.9kg were obtained from 1,351 tonnes of ore, but records are known to be incomplete. Drilling by the Department of Mines in 1969 showed that the reef persists to depths of 80m, but failed to intersect significant mineralisation.

At Long Tunnel Mountain, 2 to 3km south-east of Kilkivan, at least eight adits were driven to prospect and develop mineralisation exposed in shallow surface workings. Payable ore was confined to small ore shoots within trachyte and diorite dykes and along their contacts with the country rocks (undifferentiated Palaeozoic slate, phyllite, and serpentinite). Recorded production is 14.0kg gold from 500 tonnes of ore. Alluvial gold was also produced from this area.

The chief gold mine on the Black Snake plateau, was the Shamrock gold mine. The Black Snake deposit lies in the same feldspar porphyry intrusion as the Shamrock, and consists of a single, vertical, north-east trending vein of quartz and calcite up to 200mm wide containing gold bearing iron-stained quartz. At least 150 tonnes of ore were mined, and assayed up to 245 grams/tonne gold. The Mariners reef, near the Shamrock gold mine, occurs partly within feldspar porphyry and partly within the adjacent metasediments. The reef, which is 260m long, strikes at 355° and is steep dipping. It contains gold, silver, chalcopyrite, chalcocite, arsenopyrite, pyrite, galena, and stibnite in a quartz gangue. Recorded production is 21.2kg gold bullion from 407 tonnes of ore. A diamond drilling programme carried out by the Department of Mines found no significant mineralisation at Mariners and only low grade material at the Black Snake.

At Gold Top, 7km north-west of Kilkivan, two siliceous reefs occupy sub-parallel fissures about 30m apart in andesite of the Neara Volcanics. The reefs are up to 1m wide, strike north-easterly, and have steep dips. Ore shoots are small and irregular. Below the water table, gold values decrease, and minor sulphides are present. Between 1911 and 1913, 213 tonnes of ore yielded 8.3kg gold.

Marodian Goldfield (13km north of Kilkivan) Alluvial gold was found on Colo Flats and at Yorkey’s Hill. Little work has been done on the field for many years. (Please view further information on this area under "Marodian Area" which follows on this page.

Tansey Gold mine

The South Burnett gold mine at Tansey Creek near Goomeri, 20km west-north-west of Kilkivan, was described by Government Geologist, A.K. Denmead. The deposit is in sediments of the Neara Volcanics intruded by trachyte, andesite, and microdiorite dykes. Disseminated pyrite and arsenopyrite with minor sphalerite, galena, tetrahedrite, chalcopyrite, proustite, and gold occur in quartz and quartz-calcite veins in sheared graphitic mudstone. In the 1934-42 period, production totalled 3,202 tonnes of ore for a yield of 40.8kg gold and 36.7kg silver. An auriferous formation was worked to a depth of 87m when work ceased in 1942.

Gold losses in the tailings were high because graphite tended to coat the gold particles and prevent amalgamation. The Department of Mines drilled the deposit in 1967-68, and in 1970, Uranium Consolidated N.L. dewatered the mine and sampled the lower workings. The results of both these investigations indicated that some sections of the lode contain significant gold values, but most of it is very low grade. Recent dewatering and sampling indicated erratic distribution of values in the bottom workings.

Small quantities of gold have been produced from alluvial and reef deposits along Gobongo Creek being 25km from Kilkivan.

MARYBOROUGH & UPPER BURNETT AREA

Proston, (116km by rail west of Gympie). Some gold prospecting has been carried out in the Boondooma area, some 32km west of Proston, but nothing of importance has been recorded.

BIGGENDEN AREA - Overview

Biggenden (87km by rail west of Maryborough). For the purposes of this report, mines within a 25 mile radius of Biggenden are generally referred to as the Biggenden area.

The Paradise Goldfield (13km north-west of railway at Degilbo), Stanton-Harcourt Goldfield (18km north of Degilbo, and Mount Shamrock Goldfield (19km west-north-west of Degilbo). Auriferous (gold-bearing) lodes were also worked at the Chowey Goldfield, Gebangle Goldfield a few kilometres further west as well as the Young Australian Gold Mine.

Some of the earliest prospecting was done about 1870 on the Chowey Goldfield, and about 1874 in the Mount Havilah area. Unfortunately, records of the activity prior to 1885 are not available. Mining activity in the area was greatest in the period 1886-1902 and by 1920 most of the fields were deserted.

A deposit of magnetite at Mount Biggenden was worked intermittently for its gold and bismuth content until 1938. In 1966 the Biggenden Bismuth Mine was reopened by Commercial Minerals Pty Ltd as a magnetite mine. This mine is now currently closed. At the present time mineral exploration in the area has been revived; several companies are engaged in the search for metals, particularly copper and zinc.

The Biggenden area has produced gold, bismuth, silver and some zinc, lead, copper, limestone, and ironstone.

Paradise Goldfield

The Paradise Goldfield, covering an area of 13 square miles, is on the southern side of the Burnett River, 12.8km north-west of Degilbo. Payable gold was discovered in 1889, and the goldfield was gazetted in 1890. By 1895 the field was almost deserted, owing mainly to the impoverishment of the reefs in depth. Approximately 15 lines of reefs were worked. In general these were very thin, severely faulted, and rarely carried more than loz/ton gold. The main ore-bearing fissures have an easterly trend. Lode material consisted of bluish quartz containing finely disseminated pyrite, together with larger grains of pyrite and rare particles of galena and sphalerite. Gold occurred as a very fine, regular dissemination in the quartz, which is probably why no alluvial deposits were discovered. The country rock consists of altered sediments of the Biggenden Beds. These include sandstone, siliceous slate, schist, and contorted lenses of limestone In the Paradise P.C. shaft the country rock is quartz feldspar porphyry. Between 1890 and 1901, 11,511oz of gold were recovered from the Paradise Goldfield.

Stanton Harcourt Goldfield

The Stanton Harcourt Goldfield is 17.6km north of Degilbo and 27km south-south-west of Childers. Alluvial gold was discovered in 1885. Rands reported that a few small leaders were being prospected, but the workings were dominantly alluvial. By 1901 the field was deserted. The goldfield is on altered sedimentary rocks of the Biggenden Beds. These are overlain by small outliers of the Aranbanga Beds. which in this area are intermediate to basic pyroclastics and flows. To the east, the Biggenden Beds are intruded by the Triassic Broomfield Granite, and to the north-west by the Triassic Tawah Granodiorite. Most of the alluvial workings were in the catchment area of Stony Creek, a tributary of Tawah Creek which flows into the Burnett River. Most of the prospected reefs are within 1 mile of the junction of Slimy Gully and Stony Gully. Ball (1901) reported that these reefs were very poor.

Mount Shamrock Goldfield

The Mount Shamrock Goldfield is 8.8km north-west of Degilbo. The principal mining centres were Mount Shamrock, Mount Ophir and Mount Melville. Gold was discovered at Mount Shamrock in 1886. Here, shales and siltstones which are part of the Biggenden Beds are intruded by a dyke of diorite 45 feet thick. This dyke occupies a fault dipping 30º E. The diorite and sediments are faulted; some of these fault planes are invaded by acid dykes. Thin acid dykes are probably contemporaneous with the Triassic Aranbanga Beds, which form outliers in the area. In the vicinity of Mount Shamrock, the Aranbanga Beds have been removed by erosion, but a volcanic vent filled with agglomerate is exposed. Fragments in the agglomerate are mainly mudstone, diorite, and acid volcanic rock. The agglomerate, shale, diorite, and acid dykes were all gold-bearing. The gold occurred in small veins consisting of varying amounts of arsenopyrite. pyrite, native bismuth, bismuthinite, joseite, chalcopyrite and sphalerite; calcite and quartz were the gangue minerals. Where bismuth minerals or arsenopyrite occurred, gold values were high; where sphalerite occurred, gold values were lower. From 1886 to 1907, 34,419 tons of ore yielded gold to the value of $226,688.

The geology of the Mount Shamrock area also applies to Mount Ophir (1.2km north-north-west of Mount Shamrock) and Mount Melville (on the opposite side of Didcot Creek to Mount Shamrock). Dunstan described both peaks as volcanic necks. Ridgway reported that mineralized veins at Mount Ophir, although rich in part, were too small to be worked profitably, and that the mining of all mineralized zones including rich veins would not be economic since the overall yield would be very low. Production figures are not available for Mount Ophir and Mount Melville. In 1870, the Chowey Goldfield, 4.8km north of Didcot, was prospected, but the field was abandoned by 1886. Here the Triassic Chowey Granite intrudes the Biggenden Beds. At the contact, the granite is syenitic. The Chowey reefs consisted of large masses of white quartz with molybdenite and free gold in association. Production of gold was very small.

Gebangle Gold Reefs

The Gebangle reefs, about 9.6km west-north-west of Mount Shamrock, were prospected about 1886 and by about 1890 the field was abandoned. The country rocks are mudstone and siltstone of the Biggenden Beds, intruded by fine-grained acid dykes, all in part overlain by very small outliers of agglomerate of the Aranbanga Beds. The agglomerate contains angular fragments of shale, slate, quartz and acid volcanic rock; it contains up to 20 per cent pyrite. A little fine gold was obtained on crushing but most of the values were present in the pyrite.

Young Australian Gold Mine

The Young Australian Gold Mine is 8km north-east of Biggenden. The area was prospected before 1901. The country rock consists of altered sediments (Biggenden Beds) intruded by small dykes of aplite and feldspar porphyry. In general, the reef dips to the south-east and ranges in thickness from 50mm to 380mm. It consists of purplish massive quartz with enclosed fragments of pyritic slate and appears to be formed by the silicification of a crush zone. Ball reported in 1903 that a crushing test on 20 tons of ore indicated gold values of 3oz/ton. Sporadic gold mineralization has been reported from the Walla Range area, 5.6km south-west of Coalstoun Lakes. Brooks reported on the Seven Sisters Gold Prospect, Coalstoun Lakes. Exploration work is continuing on the prospect. Gold mineralization in the Walla Range area is probably genetically related to movement on the Perry Fault; a silicified fault breccia intruded by small aplitic bosses and dykes