Any ideas on this ID?

[stdenis_jd]

Thinking chrysocolla, but seems pretty soft.. maybe something similar? Hardness 2.5-3.0 (copper barely scratched it, fingernail won't)

 

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[Eu_citzen]

Do a streak test to confirm.

 

[stdenis_jd]

Well this is confusing. The hardness is definitely not higher than 3.0 and the streak is light green indicating malachite but malachite according to the books starts at 3.5

 

[stdenis_jd]

I chiseled off a clean piece and it's lime green through and through

 

[Eu_citzen]

Well this is confusing. The hardness is definitely not higher than 3.0 and the streak is light green indicating malachite but malachite according to the books starts at 3.5

Chrysocolla starts at 2½ in hardness. So that fits the description, IMO.

The images look blue-green to me, also a match for Chrysocolla.

 

[stdenis_jd]

Interesting, cool man appreciate the help. In your opinion, is such a soft, granular sample a good idea to try to cab/polish? It's big enough I could easily get 3-4 slabs just wonder if I'd be wasting my time or if it's worth a shot. Not very special in the rough so I suppose I have very little to lose by trying at least...

 

[Eu_citzen]

I'd saw off a sample and get it wet with water. If the color is nice, I'd try cutting it. Just not use it for rings; such soft stones don't fair well in rings.
I always to a first test cut of new materials to learn/see it's perks.

 

[stdenis_jd]

Good advice for sure, soft rocks worn as rings cannot end well haha...thanks again EU

 

[Eu_citzen]

Glad to help! I'm gonna be doing some test-cutting myself today.

 

[stdenis_jd]

Here's what came out of this rock

 

[Eu_citzen]

Nice!

 

[IAMZIM]

That's awesome! Thanks for sharing it!

 

[stdenis_jd]

Nice!

Thanks for helping ID it for me EU...turned out a lot better than I thought it would. Didn't think it would hold up to the diamond without undercutting or chipping badly but it endured pretty well

That's awesome! Thanks for sharing it!

Thanks Zim, always cool to see what a dusty old rock will turn out when cut & polished!

 

[Eu_citzen]

Glad to help. What did you polish it with? Diamond or tin oxide? Tin ox seems quite good for softer stones, like that one.

 

[stdenis_jd]

Yean SnO2 is my go-to now. Even with harder minerals and rocks it seems to work great so I start with that when experimenting and if that doesn't give me a good enough shine I move on to the recommended/orthodox type polish. I was surprised to see it work very well on some rhodonite cabs I just polished, thought I would need to use cerium or diamond but the tin worked great.

Oh yeah to answer ur question directly, haha, I used tin oxide on smooth leather. About 50/50 wet/dry. I wet the leather and ran it until dry and continued for ten seconds or so, cycled about 6-7 times

 

[Eu_citzen]

Jupp, it's my go-to also. My felt wheel is dressed with both diamond (middle) and tin oxide on the outer edge.
So it's a quick jump to either, when one fails.

 

[hvacker]

After a suggestion I used contact cement to attach a piece of commercial type carpet to a piece of round plywood.
I fit it to our cab machine. Using tin oxide paste the results were good.
Works well for soft stones and ones that were stabilized.

 

[stdenis_jd]

After a suggestion I used contact cement to attach a piece of commercial type carpet to a piece of round plywood.
I fit it to our cab machine. Using tin oxide paste the results were good.
Works well for soft stones and ones that were stabilized.

Oooo...carpet sounds like a great idea actually, think I'm gonna try that. Seems it will hold the oxides better. What general type of carpet? Thin or shaggy or in between? Does it build much heat/friction?

 

[hvacker]

Oooo...carpet sounds like a great idea actually, think I'm gonna try that. Seems it will hold the oxides better. What general type of carpet? Thin or shaggy or in between? Does it build much heat/friction?

I used a thin commercial type similar to Berber. Something like a floor mat should work. Things will get hot rather quickly
but mostly just your hands. The example I saw made by another caber made the wood bowl shaped as that conformed
to the stone better. I think I saw the idea on a rock cab site.

 

[hvacker]

Oooo...carpet sounds like a great idea actually, think I'm gonna try that. Seems it will hold the oxides better. What general type of carpet? Thin or shaggy or in between? Does it build much heat/friction?

I used a thin commercial type similar to Berber. Something like a floor mat should work. Things will get hot rather quickly
but mostly just your hands. The example I saw made by another caber made the wood bowl shaped as that conformed
to the stone better. I think I saw the idea on a rock cab site.


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