Jump to content
Nugget Shooter Forums

Mystery mineral


Recommended Posts

I believe I picked this up in the Belmont mtns.

Very heavy, black streak test, not in the least bit attracted to a magnet. I took a grinder to it which did little but polish a bit. No sparks, didn't fracture or leave dust.

Not ilmenite, magnitite or graphite.

Probably something obvious designed to trip me up.

0409190817.jpg0409190817a.jpg

above is where I used the grinding wheel.

Link to comment
Share on other sites

4 hours ago, ArcticDave said:

I'm guessing a variety of copper sulphide. Maybe chalcocite, or even covellite. I have a chunk of covellite here, that is so dark indigo... it's almost black. Since the picture makes it look grey, I'd lean towards chalcocite.

Covellite leaves a grey streak though. Going with chalcocite. Now, where's my acids, hmmm

  • Like 1
Link to comment
Share on other sites

How hard is this piece? Both chalcocite and covellite are quite soft and both will ring loudly on a detector. The top photo

looks brown on the end is that so?

Link to comment
Share on other sites

It's very hard, not black but gives off an interesting silver/ blueish metallic hue. 

I read chalcocite is mildly magnetic when heated. ..hmmm

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...