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Mike Bullivant's Diary

Day 8: Properties of Gold

Mike working with the sluiceThe whole team's come down to the river with us this morning, which means we can double the scale of our operation. Mike knocks up a second sluice box, and we all lay in to a morning of backbreaking work. Gold fever takes over, which is just as well because it's raining even more heavily today, and our ‘waterproof' clothes are still damp from yesterday. We happily call it a day at lunchtime, carefully dismantle the sluice boxes, and take the recovered punga bark back to the sawmill. We aim to burn the bark, something that will have absolutely no effect on any gold that's been trapped in its fibres. What we'll be left with is a pile of ash containing any gold we've managed to collect. It'll then be a simple process to separate the heavy gold grains from the ash, using the same panning technique we used on day one. That's the theory, but it turns out that the punga bark is so wet that it's extremely difficult to burn.

Kathy and Mike weigh goldIt's late afternoon on the final day of the challenge, and we're just not going to have time to extract our gold from the bark. We have to settle for using Kathy's balance to weigh the small amount of gold that we managed to retrieve from the panning on day one, which we've combined with the gold recovered when we carefully washed down our sluice boxes this morning. Even so, Kathy's balance indicates that we've managed to extract 0.55g of gold, albeit impure, and this is confirmed by re-weighing it on the ‘more-accurate' top-pan balance that Kate H has brought along. Not a lot of gold to show for all that hard work, but very satisfying, nevertheless. And we still have what we hope is the bulk of our gold still temporarily trapped in the punga bark. There's no way of knowing what our total yield will eventually be. If we can get more than half a gram from just a few pans and the box washings, I'm confident that we'll end up with a few grams of the stuff; certainly enough to work with in future programmes.

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Photo: Mike Bullivant
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