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New Set to Figure Out
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5/15/2018 12:55 PM
Thanks, Daniel, that is helpful! I noticed so many of these were pretty hard and showed no streak on white, those factors weren't that useful. I have trouble deciphering cleavage and fracture that I'm not good with those yet.
The slab shown in D is an interesting one, I need to get a picture in the light or bring it to the next meeting. It's definitely got some material captured inside what looks like very clean quartz or something. The material inside reminds me of dead moss.
5/13/2018 11:18 PM
A is a palm root that has been agatized
the green does seem to be malachite
B is Paral Dendritic agate or similar.
most jasper are 6.5 to 7 and most agate is 7 to 7.5 - streak and hardness do not help much to distinguish jasper form agate from quartz
these tests can help id dolomite or things like malachite. Even obsidian is a 6 and so is opal - so often hard to tell apart form other quartz by test - have to count on look
5/12/2018 7:34 PM
Ok, attached is a new set I'm trying to figure out. I did more work trying to figure these out but most of it did't help me much. Pictures include dry and splashed with water. The one labeled D does not stand out well in the photos, but I'll give more detail below.
A.) A brownish white slab that is smooth to the touch. It showed faint scratches with a steel knife, so maybe a 5 or 6? Either no streak or white. I tried to figure out some other points like fracture and cleavage, but most of those I cannot tell yet.
B.) Light grey and black, speckly and maybe dendritic? Small slab, mostly smooth. No streak or white. Maybe a 6 hardness? It scratched with a piece of sharp quartz but not softer thing like a penny or a piece of fluorite.
C.) Brown/black, smooth slab. Interestingly magnetic in the darker areas. No streak and I couldn't scratch it with anything I had including quartz.
D:) Dark brown and mottled looking with translucent patches. This one did not show up well in the pictures, but if it's wet and held up to light, you can see right through parts of it and it looks as though something is trapped inside like a brown dried mossy substance. I got a brown streak from one side of it but the other areas didn't make a mark. It was pretty hard, I had trouble scratching it with anything.
E:) Dark green, smooth and banded. Really pretty banded green when wet. Green streak. Barely scratched with a sharp piece of fluorite. Compared to some polished pieces I have, I think this is slabbed malachite.
Any suggestions very welcome! I'm finding it very hard to identify anything using the web, apps or books. I can identify some really basic things but there are so many I still have no clue about.
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