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Author Topic: How to test rocks to see if gold looking stuff is really gold?  (Read 71400 times)

huntin4gold

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is there a way to test my crystals to see if i have found gold? i have found some that I'm positive is pyrite but i have also found some that totally looks like gold but what do i know.... i read about some makeup trick where you put foundation on the back of your hand and then run the gold on it and if its real it will leave a black mark, i don't really want to do this with a rock cause it would probably leave a mark from dirt.is there some kind of test that i could buy or some other way of knowing? if i went to a mining shop would they know? I'll try to get some pics up, ,maybe someone could tell? Ive read a lot of the posts on here pertaining to gold and i must say- you all are very smart and knowlegable and i look forward to any advice you can give me. one more thing- i especially loved the melting Neil post and the ram head poop!
« Last Edit: 09/03/2008 16:12:53 by ukmicky »

elegantlywasted

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You could bite it. Pyrite is harder than gold, and I'm pretty sure gold is malleable enough to bite into.

paul.fr

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a handsome young man asked a similar question, here:
http://www.thenakedscientists.com/forum/index.php?topic=9797.0

JimBob

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Please describe your crystal. Does it have rods in it?


As for Paul, he is really ugly and just can't accept it.

paul.fr

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As for Paul, he is really ugly and just can't accept it.

I will have you know, that i won 2nd prize in beauty contest whilst playing monopoly! Also i think i am the most handsome man here with the username "paul.fr"....so there.

huntin4gold

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now now boys, im sure your both very handsome LOL 

 my computer keeps freezing up when i try to view your other post paul :(

 jimbob please forgive me but i am what i would call a geology virgin and dont know sh*t, what do you mean by rod?

by the way i was gonna put some pics up but my camera sucks and was not capturing anything worth a damn.

huntin4gold

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ok here goes my description (keep in mind that i never won any awards in school for most descriptive writing LOL)
 
outside is pretty smooth like,doesnt have any beautiful pointy see thru rocks like the ones you make jewlery from,on one side it has what looks like cuts in it one of them looks like someone cut a chunk out of it. 2 of the sides have little holes all over them and thats where the gold looking stuff is,its not nuggets or anything just flakes but lots of them and the color is sort of a pinkish gold.

Bass

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Can you describe the rock any better?  Do you know if it is igneous? metamorphic? sedimentary?  Can you see distinct layering or crystals?
How about the little holes?  are they smooth or can you see any crystals in them?  Any iron oxides (yellow brown to reddish brown)? 
Are the flakes flat?  If you try to scratch them with a needle, do they disintegrare? if so you may be looking at phlogopite or sericite (different kinds of mica that can appear pinkish gold)

JimBob

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The groves suggest that the bigger part is a crystal of some sort.

Have a digital camera?

Andrew K Fletcher

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Can someone identify these impregnations in what appears to be oilslate with a soft crmbly graphite texture.











Bass

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Andrew, those look like pyrite- there are several that appear to be cubic, which is the preferred crystal habit for pyrite.  Because carbon acts as a reductant in organic rich rocks (coal, oilshales, graphitic shales, etc), sulfur and iron are commonly precipitated as pyrite.  The pyrite may occur as cubes, disseminated boytroidal masses (evidence of biological precipitation), and irregular masses.

Bentherdonthat

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you can take some I think hydrochloric acid put a drop or two on it if it floats it is a impostor.
Or take it to a pawn shop where they have testing sand stones and have them test it by scraping a sample on the sand stone and then applying some acid.

JimBob

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No, that is an impossible answer ben. 

Andrew K Fletcher

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Bass, Ben, Jim thanks a lot, thought it was pyrite also. Got some more samples from same place that look a tad different, more pink. Think I need the acid test to make sure though. Will report back.

Great to have some sound advice :)Looks like I am not going to be a millionare after all :P

Andrew

techmind

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is there a way to test my crystals to see if i have found gold? i have found some that I'm positive is pyrite but i have also found some that totally looks like gold but what do i know.... i read about some makeup

Has someone missed the obvious, that metallic gold is not likely to exist as "crystals" (crystals; flat facets, geometrical angles between facets etc).

Real gold would, of course, form an amalgam in mercury (one old-fashioned way of extracting gold from rock-slurry). A quick splash would at the least change the surface of the gold permanently silvery-grey. Not that you should be splashing mercury around these days... (and certainly not near any jewellery)  ;-)

See also: http://en.wikipedia.org/wiki/Amalgam

huntin4gold

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Sorry guys i havent been on since my last post, too much going on around here. ok let me start with
Bass:i dont remember back to school when we learned about igneous, metamorphic, sedimentary -What can i say, i'm lame....
There are layers of flat flakes, yes they break off and disapear when you poke them... Dang, its mica?
Jimbob: I do have a digital camera but my daughter got ahold of it and messed up the lens.The pics i took came out like crap,i couldnt get a close up that was in focus.thats why i didnt post them.
Andrew i found the exact same looking rocks at my storage unit,it made me want to prospect right then and there!
TechmindDidnt i meantion that i'm lame and dont know anything?LOL i didnt know what a amalgam is(i do now-thanks for the link to wikipedia ;)), nor did i know they used mercury to extract the gold...isnt that dangerous?

looking and finding gold for someone like me (who knows didly squat) probably isnt the best match but i like the idea of getting rich quick- lucky for you guys i found some gold test drops(should be here monday) so i wont bug you with every rock i pick up.
Thank you all for your responses  ;D

JimBob

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They also use prussic acid - cyanide

Bored chemist

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Fool's gold will burn in a blowtorch flame producing lots of stinky sulphur dioxide, real gold won't.

Andrew K Fletcher

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Dang so obvious now youve said it :) Blow torch I have :)

Karen W.

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Panning for gold is fun. You can build your own sleuth box and do it yourself and pan it is a lot of fun!!!!!

Andrew K Fletcher

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Doh didn't burn and no smell???

Dang so obvious now youve said it :) Blow torch I have :)

Bored chemist

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It looks interesting.
No smell, even red hot in air?

JimBob

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Andrew, where did you find this rock?

Andrew K Fletcher

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Found in Oil Slate in Devon UK Jim

Going to take some down town to a friend who has a jeweler repair business. He is very knowledgeable and should be able to test it further for me.

Andrew K Fletcher

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Just got back from the little jewellery repairer, who tested the rock using acid, confirmed there is definitely a percentage of gold in the rocks, except it is of such low volume it would require a huge process in order to extract sufficient quantities. Apparently if it was not gold it should have turned green with high strength acid, observed to be giving off serious vapour even before it made contact with the rock. Anyone know where I can get my hands on some dynamite?

 

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