I have a similar crusher but on a smaller scale and I fabricated a solid cylindrical piece of metal and welded a shaft to it that fits on my power drill, with it I can grind materials as fine as talc powder in no time at all.
This was very helpful. I roasted mine and exoected them to turn red so when they turned black i considered it a fail and chucked the lot. Now i realise where i went wrong.
After roasting and grinding, spray it down with concentrated hydrogen peroxide. The kind used in plumbing! I had this same thing happen to me with my ore. After I let it oxidize it seemed to release nanao fine gold!
One trick I've heard is to take your black sands immediately after roasting and put them in water. I was told it shocks the black sand creating fractures and aids in crushing. Also, no oxidizer for the roast? Doesn't that help with sulfides and freeing up the gold?
Thermal shock should do well to help, probably should have tried it. I roasted a thin layer of fine material for 30 minutes with air. It should have done OK. I haven't researched oxidizers yet, but I am sure the right additive would speed things up.
It may not seem significant at first but under normal panning at the end of the day one would have thrown out @50% of the gold you have shown in your pan. That little bit is a lot over an entire season. No one that I know will roast and crush their cons. Lesson learned. Thanks.
Hard Rock University I should note i am not referring to commercial operations. I’ll use myself as an example. After a day of highbanking , panning the cons roughly then run through a small clean up sluice and suck it up with a snuffer. Any cons trough the clean up sluice gets tossed. But if I roast and crush I should get a little more gold.
@@solobushman It is hard to tell. This test was run on gravity concentrates from a hard rock gold vein. Because it came from bedrock the original sulfide minerals had not all oxidized. There appeared to be significant arsenopyrite and some chalcopyrite in them. That is what I was roasting for. If the placer deposit is near the bedrock source (mother lode), then it may be useful to roast. More often you would only have a potential benefit from finely crushing placer concentrates. It is worth a test in most cases to do so.
Great video but I have the following question: If you already oxidized your sample by roasting it, once the iron is oxidized the gold should be unbonded and free so why did you had to crush your sample again?
That mystery material looks near identical to a heavy fraction in concentrates I've been taking from a NW Montana placer mine. At first I thought it was a reddish brown clay, then noticed it's far too heavy to be clay. Could it be *Hematite? (Sorry about the edits, couldn't remember at first what I thought it might be. Asked the mine owner if he thought that's what it is, but he didn't know.)
How are you guys doing I am once again getting ready to head for the field what did you use for the hammer part of crusher any tricks to busting up hardpan
A solid steel ball welded to a pipe handle. An electric demolition hammer and generator make digging tough soils very easy. Even a harbor freight makes it easier. My Hilti was bought for bedrock and quartz veins.
@@ChrisRalph Possibly. 20-75 ppm Pb in previous samples. That might do it. I really want to spend some time taking classes in minerology, geology, and orogenesis- it gets so annoying to be so ignorant at times. :-)
zircon sand .i asked the same question once ,what is that silvery residue sits on top of my black sand , zircon sand ,then i checked it with a 60x jewelers loop ,and yes it was ,looked like quarts ,but it's heavier .
It depends on the form of the gold. Very fine gold, if not flaky, will settle THROUGH the magnetics to the pan while you wash the rest off. Then, when you remove the magnetics, there is little left but gold. Flaky gold will not behave the same.
@@hardrockuniversity7283 Oh So then why not just smelt it in to a button? Is what I was considering. I have 2 different Types of specimens I am working on. Both I believe to be Sulfides. ** One is 29.5 lbs, non magnetic and it has visible Gold vanes. grey and red and black and browns and metallic colors. I tried cutting with the hacksaw and I filmed it I'm going to post that to my RU-vid channel. Because I have that specimen uploaded to my channel already. One of my most recent the iron stained Stone I haven't uploaded yet but I will and the process of getting it down to fine grain dust powder with a flour like consistency. All with my home made mortar and pestle DYI. Rock Crusher. **The other was 7.4 lbs. Iron staining is prominent thru out the specimen. I say was cuz I broke it down into handful size pieces and smaller and crushed half of the specimen into dust
@@DR_SOLO It would depend on what equipment you have and how much gold there is. If you are set up for it, smelting is an option. I wasn't set up then, I can do it now if I wish.
Eva is doing great. Money is OK. The truck is in the shop as we speak. I am planning on flying to AK this summer and bringing Eva up if it works out. How you doing?
While it would certainly work on a small scale, the cost and waste disposal on a production scale would be prohibitive. It is not an experiment for the fun of it, it is a small scale test to see if it works before worrying about scaling up if it does.
