Welcome to the Rock Tumbling Hobby Forum where we share a love of rocks and a sense of community as enduring as the stones we polish.
The RTH Forum of www.RockTumbling.com is an Amazon Associate site and we earn money from
qualifying purchases you make after clicking on our links such as this
Rock Tumbling Supplies on Amazon
link for instance, or any of our various product ads and banners. By clicking our links every time you begin your Amazon shopping
experience, you are generating a bit of revenue for the forum which helps us cover our expenses. Thank you for your support!
If you cannot see Amazon ad banners directly below this text, please whitelist this site in your ad blocker(s). The ads below have been hand-selected for relevant content, and your patronage directly benefits this forum community, thanks!
That's lovely stuff Tommy. I don't blame you for wanting more. Somehow those copper-related minerals seem to show up in truly odd combinations. For example this piece, which appears to be either chrysocolla or turquoise filling in spaces in a very hard black breccia. It's pretty but a real challenge to cut because of the hardness difference.
Seriously though thank you Scott - when I started grinding on it and it turned everything black - having never heard of CuS I immediately stereotyped it as hematite.
Edit: I should have thought it through - hematite would not shine silver like that. It can shine but it's different.
I would strongly suggest not covellite....While I am not an expert on anything, I have a fair bit stashed away from Butte, MT and none of it resembles this. Regardless, an amazing cab and killer material. Cheers
Last Edit: Mar 20, 2017 22:39:09 GMT -5 by bsky4463
So why would it grind silver and cab black? Does the polishing heat oxidise it? CuO is black; think to black firestain in Sterling Silver. CuS - IS Covellite and that is also black: link
Post by rockjunquie on Mar 21, 2017 10:23:44 GMT -5
Broke my internet, too. Never did see it. However, I had a cab exactly like yours, years ago. It has since been wrapped and sold. Sold quick, too. I never did figure out what it was, but it was awesome. The metal was in a more paisley pattern, but it was the same way- black shiny metal and beautiful chrysocolla. Have you considered that it might be shattuckite?
I definitely vote no on covellite. Not remotely the same. The covellite is very dark indigo blue with a sheen.
Thanks Tela it's entirely possible based on one factor - the vendor I got this from sells a lot of shattuckite. The reason my mind didn't go there is I picked this from a scrap bin of small pieces of shattuckite and it stuck out like a sore thumb. None of the other pieces looked remotely close to it - or had the black metallic stuff.
Luckily I have a small scrap piece left from this. If I do a streak test shattuckite should streak blue vs. chryso streaking white to light blue - according to www.minerals.net
OK I did some streaking around the house. Boy wasn't momma surprised .
The blue/green streaks blue green ruling out Chrysocolla I believe.
The black streaks black with a green tinge...the green could be influenced by the blue/green influence but hematite is ruled out and pyrite is a strong possibility.
This space is for temporary chat only and all posts drop off automatically and are not saved.
Members with real questions or comments that need an actual response, please post on the main forum - not here! Casual PG-13 posts only, no politics or religion please!
1dave: werejen, you are in the wrong place.
May 7, 2024 9:59:24 GMT -5
ThomasT: The rare Double brood of Cicadas coming out now... last time this occurred Thomas Jefferson was President...
May 7, 2024 17:42:04 GMT -5
ThomasT: Cicadas 13- and 17-year emergence cycles align only once every 221 years... much rarer than a solar Eclipse. Next event will be in the year 2245 AD. Woohoo
May 7, 2024 17:55:50 GMT -5
ThomasT: Buy your tickets now... once in a lifetime
May 7, 2024 20:16:09 GMT -5
Wooferhound: why aren't they making any noise
May 8, 2024 12:11:59 GMT -5
ThomasT: Too early yet... I'm sure they will get pretty loud this summer.
May 8, 2024 13:14:48 GMT -5
*
amygdule: The crispy fried Cicadas don't make any noise until you chew on them
May 8, 2024 14:10:18 GMT -5
Wooferhound: The last person that quit or was fired will be held responsible for everything that goes wrong -- until the next person quits or is fired.
May 8, 2024 16:22:09 GMT -5
liveats14rocks: the fox has entered the glade
May 8, 2024 17:46:23 GMT -5
RickB: Welcome to the board. You are just in time for appetizers
May 8, 2024 19:25:39 GMT -5
*
Wooferhound: it's Cicada me if its Cicada you
May 8, 2024 20:40:29 GMT -5
1dave: To fix any body problem Just place a spoon on it and tap with another spoon. The WEB has spoken!
May 8, 2024 21:54:09 GMT -5
Wooferhound: I Like Spooning
May 9, 2024 5:42:33 GMT -5
thestripedone: I've been using ceridium oxide for my 4th step of polishing. I was wondering if there is a 5th step for a super polish
May 10, 2024 17:20:10 GMT -5
amygdule: Silicon Carbide SiC grind in Rotary then Aluminum Oxide AO polish in a vibe...
May 10, 2024 17:37:12 GMT -5
*
Welcome to the Rock Tumbling Hobby Forum where we share a love of rocks and a sense of community as enduring as the stones we polish.
The RTH Forum of www.RockTumbling.com is an Amazon Associate site and we earn money from
qualifying purchases you make after clicking on our links such as this
Rock Tumbling Supplies on Amazon
link for instance, or any of our various product ads and banners. By clicking our links every time you begin your Amazon shopping
experience, you are generating a bit of revenue for the forum which helps us cover our expenses. Thank you for your support!