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GOLD OCCURRENCES IN QUEENSLAND
Geological information on the old
goldfields of Queensland provided here is taken from the Department
of Mines in Queensland and the Bureau of Mineral Resources in
Canberra.
This edited information comes from
early Geological Reports, Mining Guides and the like which have been
written by the various Government Geologists at the time.
This subject is divided into three (3)
regions as follows:
- Southern Queensland
- Central Queensland
- North Queensland
Just go to the left-hand side column
of this page and 'click' on to the region required.
Please Note:
All mines and reefs that were named within the above
regions are shown in Green
Italics.
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G O L D
INTRODUCTION
Its
widespread occurrence in a great variety of ore deposits throughout
the metalliferous areas of the state of
Queensland
makes gold a mineral of primary interest in the operations of the
prospector. It may occur as native gold or lode gold, by itself or
with other metallic minerals in sulphide ores (such as: pyrite,
chalcopyrite, arsenopyrite, galena, and sphalerite) or as tellurides
in many widely different classes of rock.
In its native or 'free' state, gold is never absolutely pure, but is
alloyed with varying proportions of silver, accompanied at times by
traces of copper, iron, platinum and other metals. Generally speaking,
gold won from alluvial deposits is purer than lode gold from the same
locality.
The physical properties which best identify free gold are its weight,
colour, low degree of hardness, toughness and malleability. Its
freedom from tarnish in the air or when heated and resistance to any
single strong acid are also to be noted. The characteristic yellow
colour of the purer metal becomes increasingly paler with an increase
in the proportion of silver present.
Despite its high density, very fine gold particles in the form of
'mustard' and 'paint' gold will float readily on water, and this
action is greatly increased if any trace of grease is present. To
solve this problem, it is generally best to add a little detergent to
the water when testing for gold or with the final 'clean-up' after
gold panning. The toughness and malleability of gold allow it to
hammered into extremely thin plates … being soft, it may be
scratched readily, leaving a streak of the same colour on unglazed
streak plate.
By careful observation of these properties gold is readily
distinguishable from such minerals as: pyrite, chalcopyrite, limonite
and golden-coloured mica are frequently mistaken for gold by the
inexperienced. An easy way to test gold in the field is to hit the
gold (make sure it's not a good saleable specimen) with a hammer and
the gold will flatten. If it is one of the other minerals mentioned,
the "so-called gold" will shatter with impact. If it is mica, the mica will
generally break into nothing when rubbed between the fingers.
In sulphide ores, gold is not always present in a free state. Therefore, it is basically impossible to identify in a gold
prospecting gold pan. The prospector needs to bear this fact in mind,
and, provided any 'tail' shows after roasting and regrinding the
concentrate; it is well to have an assay made of a representative
sample of the sulphide ore before accepting it as worthless.
The presence of gold in the form of tellurides may easily escape
detection, although gold tellurides are not common in
Queensland
. They are highly lustrous minerals, silvery-grey to pale
bronze-yellow in colour, and are soft and very heavy. Some of them in
general appearance are not unlike molybdenite or flaky graphite.
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NOTICE
No
attempt is made with the information provided here to deal with the
past history of the various mining fields or to describe the many
mines being worked in the State. The object rather is to show - both
to the individual prospector and to the mining investor - some of the
mining possibilities of each of the districts mentioned, passing
reference being made to particular mines in certain cases only. Slight
reference only has been made to geological features. The relative
importance of deposits and districts mentioned cannot be gauged by the
lengths of the references in these notes. On many of the old fields
the conditions are well known, or can be ascertained at the main
centres. Special attention has been drawn to some of the lesser known
fields.
Any person or company desirous of obtaining further details in
relation to any of the mines, deposits, or localities referred to
should communicate with the Department
of Natural Resources, Mines and Energy, Brisbane, or with the nearest
Warden, Inspector of Mines, or District Geologist.
The Reworking
of Deposits
The
fact that certain ore-bodies were worked years ago and were abandoned
does not necessarily imply that such deposits cannot be worked
profitably under different conditions. The metal market is always a
primary factor in deciding the success or failure of mining ventures.
The utilization of modern methods or mining and treatment may bring
renewed life to some mines.
Some
of the causes of work have been discontinued in mines are as follows:
-
Want of sufficient capital to explore and develop deposits
thoroughly
-
High cost of transport of ore to treatment works
-
The premature erection of costly plants at mines before requisite
values and quantities or ore have been proved.
-
Failure in prosperous periods to build up a reserve fund for the
express purpose of carrying out further developmental work
-
Exceptional conditions such as drought, flooding and labour
difficulties. Any person wishing to investigate the further
possibilities of any worked deposits or desiring to renew in any
locality the search for any particular mineral should weigh all
the known factors relating to the closure of previous workings.
Some of the factors may be gathered from these notes; others can
be obtained from official records or from officers of the
Department of Mines stationed on the various mining fields.
Fresh
Discoveries
Although
most of the larger and more obvious outcrops of mineral deposits have
been located and tested to some extent there are still possibilities
of new discoveries within the metalliferous areas of the State. The
fact that in these notes some localities are mentioned as being worthy
of further prospecting does not indicate that the other localities
referred to should not also be prospected. The special mention is made
only in cases where some of the factors making for success are known.
E. & O. E.
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