Black silver sand...?

[Prospector B]

So I have been crushing some rock which contains a few small pickers, after panning the crushed rock and removing the black sand and also the dolly pot steel with a magnet I was left with the following.

I dont have much experience with normal black sand because I've not found a heap of it in the creek where I found the rock I've just crushed, is this just normal black sand which has gone a bit silver like because I've crushed it, or something else?

Interestingly apart from the two pickers which fell out of the rock before I crushed it there does not seem to be other gold in the rock.

Photos were taken through a 30x loupe.

 

[user 1769]

Haematite?

 

[Hare_Twigga]

I would imagine it's part of your crushing device,it will most likely be magnetic. I have a magnet attached just before the sluice on my crusher so it picks it out before it gets mixed with the gold concentrates.

 

[Prospector B]

Hare_Twigga, I have already removed the magnetic bits with a magnet.

Thanks mfdes, it could be Hematite.

 

[Ben78]

Arsenopyrites

 

[Hare_Twigga]

I thought hematite was magnetic? whats your crusher made from?

 

[G0lddigg@]

graphite?

 

[gcause]

That bigger silver nugget next to the small gold sliver may be gold covered in mercury. Just a guess hard to tell from the photo.

 

[Ben78]

All the silver-black stuff in this pan is arsenopyrite bonded with gold - super difficult to separate the two, even a blue bowl wouldn't do it.

Arsenopyrite is super common in association with gold bearing quartz reef in a lot of areas.

 

[Prospector B]

Hare_Twigga, the dolly pot is just made from steel and I thought hematite was magnetic too.

Ben, I think you might be right. I had a quick Google on arsenopyrite and some of the pictures look really similar to what I have. According to Wikipedia it should smell like garlic when i crush it!

G0lddigg@, does graphite occur with gold?

gcause, Ill leave the silver bits in my pan and see if they spread or migrate. It will me mercury if it does.

 

[Drbean]

Had the same stuff after sluicing and panning .man hard
to shift it so I built a wave table just a small one and put
1.5 mm rubber black not rippled mat at 5 degrees angle.
This worked a treat .I've since put a head shaver under
table to vibrate the table .
What ever you do do not try and melt it .I learnt the hard
way it doesn't like that ohhhh no! Dr.

 

[Ben78]

Nitric Acid breaks it down - but I decided it was better for my health to pick out the bits I could and turf the rest

 

[Barra_Mad]

There is a couple steps to go through to identify a mineral firstly how hard is it will it scratch glass or will glass scratch it, If it is arsenopyrite it should be 5.5 - 6 on the MOHs scale meaning glass should scratch it. next make sure its dry and try get a streak on a white and a black surface it should streak dark grayish black.

But going on the size it might be hard to test the sample but its most likely a sulfide which include your pyrite family, but knowing the part of the country you found it and reading a geological survey focused in or around the gold rush in the area should tell all the other minerals found in your rock, which will give you a short list to work off.

here is a good place to start for reports
http://www.farlang.com/view_pages_by_tags?tag=Gold

 

[Prospector B]

Thanks all, it sounds like it is some type of pyrite and not something else more precious. Thanks all for the input!