How fine to crush rock for panning

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With some assistance from my partners pops Ive welded a diy dolly pot (? I think thats the name, its just a steel tube with flat base and a very heavy rod to smash with), was quite fun.

Anyways I brought some rocks back (ironstone and quartz in a hardened clay) and crushed the heck out of them then tried panning. Well Im not sure but I dont think there was any gold in them, but I dont think I would have been able to spot it if there was. I crushed the rock till it was dust, I dont think I could have crushed it more.

I did see a couple tiny specks that looked like gold but they were seriously tiny, Id need a microscope to see if they were gold.

Did I over do it? How fine should I crush? Different size particles for different types of rock? It *was* fun to crush the rocks so thoroughly but perhaps its not the way to test your rock samples :)
 
Tent King on YouTube has a video somewhere where he crushes, runs it through a dry blower then pans it out from memory ? Worth a look if you can find it
 
I think it really depends on the size in your host material.
A lot of crushers etc relied on micro stuff.
Then as usual, it comes back to yield.
Most gold out of quartz say was invisible to the naked eye.
And that was just an accepted standard.
Fact... the more you refine it.... the more micro gold is released.
Small time hobby stuff.
Keep your material in bucket batches.
If it proves to be worthy to refine more...
Turn it to talc.
Get zip from that bucket.... chuck it...
Label your samples, eg... where you got it exactly etc.
Find an interesting peice of host... photograph it well before crushing it.
Learn from your photos, area and results.
Later on, build up to making a nice recovery sluice using Dustin's micro dream mat for recovery.
Won't wrong with his mats.
Cost is bugga all in reality
 
Watch out for those clays haha, can be a tricky thing to stop them trying to take the gold away.

DWT always said "Agitation and duration" and he wasnt wrong.
 
I had a heap of specis accumulated over years of prospecting. A few years back I got tired of looking for that mystical buyer who I was told would "pay a premium for gold specis" so I decided to crush them all up and sell for the gold.
I have a decent hand mortar and pestle and had previously crushed a number of them to extract larger gold bits but had always kept the crushings as I felt there was still more gold in them to be extracted.
I then bought one of these, well not the brand in the picture but a similar one. It turned the rock crushing to absolute powder. I found that it was still best to do a hand crush first then load the smaller pieces into the crusher and it did the rest converting them into powder.
That is when I first saw how much fine (mustard) gold there can be in quartz.
Now I'll have to be honest that I don't think that I got as much extra fine gold that justified the cost of the crusher but that was only because of the volume I had to put through.
So my reply to the post question is to crush as fine as you possibly can, the finer the more gold you get although the finer the gold the harder it is to separate but that is another topic. If you can only crush by hand it will probably never be fine enough, so throw all your crushings into a plastic bucket and keep (years if necessary) until the time that you will have an opportunity to use something like these angle grinder crushers.
 

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yep, there is alot of very fine gold in the rock/quartz after you have picked the bigger bits out.

I built my own crusher with an angle grinder to drive it, works great.

Yes break the quartz down to like the sizes in the pan beside the crusher and it turns it to powder
 

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All those pictures of a bread mix but no picture of a pan of gold, you should proove what you got.
 
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