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Guide to Fossicking in Australia
Glenalva Central QueenslandAre you interested in fossicking for gemstones? Or are planning a trip around Australia and want to explore and experience Australian Gemfields. Are you unsure what's needed to get started? A good place to start is your local Gemstone and Lapidary club, in addition read on to find out how we locate gemstones and what equipment we use.
Fossicking Methods
Where to Dig
For the Beginner, the most important step is to identify a preferred area to dig. In designated fossicking areas, this is easily identified. The Queensland Department of Mines and Energy has designated tracks of land where Gemstones can be found. Many fossickers who have been there previously have dug holes in productive areas. Choose a hole not occupied by others and clean it out or extend the hole leading toward virgin ground. To know if the hole is occupied, it is common practice to leave a bucket or similar in the hole. This is a well understood unwritten rule in this area.
Diagram of Different soil levelsAt the face of the hole you will notice top soil which contains vegetation; the sub-soil that supports the top soil, and then a rubbly or friable band containing iron stones, small pebbles and maybe medium sized basalt rocks. This is known as the wash and is the remnants of an ancient creek or river bed. All of the above rests on a bed of clay. It is in the wash that the sapphire's and other gemstones are found. Experienced fossickers will readily identify the geology of the area and investigate other potential gemstone bearing wash.
Extracting the Gemstones
The Willoughby / Sieve Method
Extracting the gemstones relies on the principle that gemstones has a greater specific gravity e.g. is heavier for given size than all other stones except diamonds. The most common method is to remove the dust from the wash, clean the stones using the sieves and Willoughby, this is commonly known as the wet sieve method. Once the stones are clean, flip the sieve upside down onto a hessian bag, or similar on a table positioned in the sunlight. Starting at the center, examine the washed stoned carefully for colour. Examine the entire contents of each sieve keeping in mind that most gemstones will stand out when wet.
Dry Sieve Method
Dry sieving is a common method used to extract Topaz. Large quantities of Topaz are associated with Alluvial Gravels in and around the creeks and tributaries and also where it has been released from the decomposing granites. Generally the wet season rains and subsequent floods tend to wash the Topaz toward the creeks and gravel deposits. Dry Sieving is the method used most frequently; we use a Shaker Box and shovel/bucket the Alluvial Gravels directly into the Shaker Box. Rocking the Box backwards and forwards rapidly soon separates out the gravels and dust. You are left with the lager pebbles and stones. The Topaz is easily identified as clear or frosty crystals or waterworn rounded pebbles ranging in size up to 2 or 3cm in diameter. The most common colours are clear (Silver) or very light blue and occasionally a very light honey coloured crystal is found but in this area mostly clear or light blue Topaz is found.
Fossicking Equipment
If you plan on spending a good deal of time fossicking for gemstones, then it's worth your while to have the appropriate equipment. The following information outlines the equipment that we use when we go fossicking.
Pick
Standard Miners pick is sufficient
Light weight scratching blade
Shovel
This is a mater of preference, between a spade and a medium sized round mouth shovel. We prefer a smaller style shovel or spade, making it easier to carry.
The Willoughby
WilloughbyThe Willoughby pictured has been constructed in parts for ease of transporting. It can easily be made by a handyman; each section of the Willoughby is outlined below.
The Stand: a 'U' section with a short vertical joiner.
The Vertical Pivot Arm: This is made from square section tubing so that it slides neatly over the vertical joiner on the 'u' section. The top of the pivot arm is designed again as a 'u' section to allow attachment of the horizontal arm. The height of this vertical section can be made to suit the person operating it, hip height is suggested.
The Horizontal Arm: Again made from square tubing, drilled to allow attachment to a vertical pivot arm and attachment of the sieve bridal.
The Sieve Bridal: This is a circular section that allows the placement of the sieves. The circular section is connected via a 'y' section to the horizontal arm. When the Horizontal Arm is moved up and down the sieves move up and down in the water bucket provided thus washing the stone.
Inspection Table
Inspection TableSimply a flat piece of Board with a piece of tubing attached underneath, this allows the table to be placed upon a steel rod driven in the ground making very transportable. The table is covered by a Hessian bag; this allows water to drain from the stones and easy clearing away of discarded wash.
Shaker Box
Shaker BoxShaker Box Bottom SectionPictures show an easy construction of two boxes 60x40x7 cm with 3mm mesh attached to one and 12mm mesh attached to the other. The lower box (which has the 3mm mesh) is made to pivot so that the smaller stones less than 12mm can be poured in to a bucket, then into the Willoughby sieves for processing.
Sieve Stand
Sieve and StandThis stand is for dry sieving, the sieves are filled with wash, placed upon the stand and shaken backward and forwards vigorously to remove dust. Generally a careful inspection follows, this is very handy for Topaz and short digs. If it is desirable to wash stones simply place sieves in the Willoughby and proceed as before.
Other Items
Buckets, water containers and gloves.


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