Wild Windellama
by Paul Alessi
July 2006
Wild Gold ! "There's gold in them thar hills" someone once said, but whoever it was forgot to mention there is a lot of dirt mixed with it, but "gold is where you find it" too, and if you look in the right place you will find gold in Windellama and of course Oallen and Nerriga as well. Many of you will have had gold fever at one time or another, maybe you found some, or maybe you just had a good time looking for it as I have done in both cases. To find gold it helps to have a basic understanding of how and why it ends up where it is. Gold is brought to (or near) the surface in volcanic events where cracks and cavities in rocks are filled with hot liquid quartz laced with gold, as the seams are eventually exposed to weathering, pieces of quartz and gold break off and are carried away with surface water to be deposited in some place always downhill from the source. Gold is a very heavy element, in fact 19.5 times heavier than water and much heavier than lead which means the big bits don't travel as far or fast as the small pieces, and large nuggets are nearer the rock that they weathered from than the finer gold. All of this has taken millions of years of weathering and geologic action and so bits of gold from one source can be overlayed on gold originating from another source thus totally confusing the issue, also large pieces that get into fast flowing water can travel faster than fine gold on flat ground, take into consideration that the slope will change over millions of years and we now we have the picture, it's all as clear as mud, but mixed with gold waiting to be found. Being so heavy, gold will make it's way to the bottom of sand, soil or gravel until it finds a solid bottom such as bedrock. Rock crevices in creek bottoms are always a good spot to look.With changes to stream flows over time a creek bottom will sometimes end up somewhere high up the bank and this is known as an Elevated Deposit, sometimes the creek bottom will be buried beneath other rock and soil and this is then called a Lead, if it's buried very deeply then it's a Deep Lead. Gold bearing rock that is in-situ is called a Reef and our area has a few gold reefs, most were mined during the 1800's and the quartz/gold ore was crushed in a stamping battery. These contraptions had a large exposed crankshaft driven by steam that lifted and dropped heavy iron weights onto an iron dolly beneath. A common arrangement was a 5 head battery much like a large upturned 5 cylinder auto engine. The crushed material was either washed down a sluice box which is basically a long box with baffles that let the lighter material wash over the top or sometimes a mercury table which had grooves across it filled with the highly poisonous liquid metal Mercury. Mercury will allow gold into it but not sand, rock or gravel so after a big ore crushing event the mercury would be boiled off and recollected leaving the gold behind in the container. The other sort of gold we have is of course alluvial gold which is the name for gold that has left it's reef and is washing downstream, much of the gold in the Shoalhaven River is alluvial and may have travelled a long way to get there, there were many large nuggets found upstream from here around Braidwood and Mongarlowe and these areas were possibly the source, also found not far away was the "Nerriga Nugget" which was 45 ounces or so which is more than enough for an effective doorstop. There were long water races in Windellama and Oallen cut through the ground to channel water to high pressure hoses that washed the hillsides down through sluice boxes, The Nadgigomar Dam off Wolgan Road was built in the late 1800's to supply water to one of these hydraulic sluicing operations and the race for the water was around 20km long passing over gullies on high wooden trestle bridges, and even through tunnels to end up at the mine site on the edge of the Shoalhaven Gorge. Some scars and relics from reef mining, hydraulic sluicing and the water races can still be found and are protected by law as historic sites. As gold travels it gets worn like a river pebble so the rougher the edges, the shorter the distance it has travelled. Much of what is found in the Shoalhaven River is so flat and fine that it actually floats on the surface tension of the water, a drop of detergent in the gold pan fixes this problem. But not all Shoalhaven River gold is this fine, a wily old prospector once showed me a one ounce nugget from the Oallen Ford area but of course wouldn't say exactly where he found it, though he did have the advantage of a modern metal detector. I've tried my hand at metal detecting too but my unit is very old and not as sensitive as the newer machines to smaller nuggets, I've never found gold with it but a lot of coins and interesting relics. The photograph in this article is of some small nuggets I found gold panning somewhere in Wild Windellama. If you get gold fever you can find "Lost Mines" and "Bungonia to Braidwood" by Barry McGowan in the Goulburn Library and "Gold Gem and Treasure" magazine at your local newsagent.
Mysterious Black and White Possums There have been two reported sightings of some long tailed black and white possums in our local area. The only animals matching this description that I can find in textbooks or online are the Queensland Striped Possum, a species not normally found in NSW and certainly never this far south. Although these sightings were many kilometres apart they were both in Windellama and both quite recently. If you've seen black and white possums or any unusual animal please contact me on 48445149.
Queensland Striped Possum (Dactylopsila trivirgata)
Copyright Paul Alessi 2006