New Zealand Gold Prospecting & Metal Detecting Forums Archive

Hi Guys... I've an idea that I thought may sound alittle out there or hey maybe an idea that may very well be worth trying. If one was to make a Gold Trap similar to a sluice that one could say Dyna bolt to bedrock on low water or secure along a bank,then after the river has flooded and water levels have lowered check your traps for some colour, what are your thoughts guys.

Rich.

Hi JW, I've been toying with the idea for awhile and thought maybe post it up here and see whether it has been attempted, I hear what your saying mother nature will play a big part and also our two leg friends would be a major concern.....

I am sure your idea has merit but it would depend on where you did it - in 1963 I think it was I worked a certain crevice in the Arrow river. I went back to that crevice again in about 1977 and reworked it and all I got was one colour. I have re examined areas I have worked in may rivers now and it has not been replenished - this would indicate that if I had a device such as you suggest in the river it would have trapped nothing as nothing was coming down the river.
I know a man made creek where the 'new' stream across a paddock scoured a new creek bed where there had previously never been one - your idea would have been good to have worked there as the finer gold did indeed wash down just as it does in a large sluicing gun claim where the cliff is being blasted away and the gold trapped in sluice boxes in long tail races...so if you have somewhere where there is new land being rapidly eroded then your idea could work.
You would have to have somewhere where the bedrock was level, you would ideally need heavy riffles like the big dredges have and they would have to be held in place securely to the bedrock by large pins driven into the bedrock itself...but yes in the right place your idea has merit. More so if you are bulldozing gravel into a swift flowing stream just up from the device and allowing the gravel to wash over the riffle plates...a similar scheme to huge sluice guns working really.
I think it would work...especially since I was going to try the same idea myself once and got the dredge riffle plates to do it...in the end I found that it wasnt worth it because where I intended doing it the gold just got trapped in the first crevices downstream in any case.

Edited by user Wednesday, 15 June 2011 5:45:41 PM(UTC)  | Reason: Not specified

Hi Lammer law,

I've gotta say I thought I may have sounded alittle crazy posting what has been on my mind for awhile now, and I'm really please to have put my thoughts out there, I value the opinions of others and to take on board the replies will have me in deep thought of way to put this idea in motion, certainly alot to consider.. Rich.

Hi Richie,

There are a couple of places down south I have come across, where riffles have been cut directly into the bedrock itself. On each ocassion, they were below a large sluiced area. I assume they had been cut in an attempt to trap whatever passed through the sluicing operation. One was out Collingwood way, I can't remember where the other one was. They were about 5 metres long, a metre wide with about 20 riffles. If you are really keen, you could do the same. No materials required, just time and a good pick.

.

Edited by user Saturday, 9 July 2011 2:40:25 AM(UTC)  | Reason: Not specified

It is a possibility but methinks it might be a lot of work for nothing for several reasons. After fifty years of prospecting for gold,mining for gold and co owning three gold claims and one copper mine claim let me assure you that not much gold is washed down rivers to replenish crevices with one exception - the erosion of a good gold bearing patch immediately upstream - the reason the old miners cut riffles into the bed was that they were going to erode huge amounts of bank and land away immediately above where they cut their riffles or shovel down large amounts of gravel which had hitherto never been worked and thus they were the first to process it and therefore it was worthwhile doing it. It is not really worthwhile doing it to merely process gravel that has been turned over and over time and time again in countless floods but it might be if you are going to erode away huge amounts of unprocessed overburden along the banks with a high pressure jet of water or a bulldozer! Even then it is far better to build riffles on the bank and fit them intoplace.
Even the old timers made faux pas and I have here a letter sent to me by a depression miner plus photographs - in an area where I was getting an average of an ounce a day they only got 2 ounces during an entire summer and the reason was that they (three of them) devoted twelve weeks to making a large dam to divert the creek - they took a photo of one of their number standing beside it the evening it was finally finished. The next photo, taken next day shows the dam - gone! It rained hard over night, the dam could not cope and got washed out. Just because you see the remains of a dam...or riffles in the bottom of a river does not mean that they got anything.

Edited by user Friday, 17 June 2011 4:23:52 AM(UTC)  | Reason: Not specified

That engine is fantastic JW! Looks like a Mitsubishi I had once!

Interesting

.

Edited by user Saturday, 9 July 2011 2:41:09 AM(UTC)  | Reason: Not specified