Help identifying these rocks and minerals please!

[sthaney]

I have a vague idea for some of these but for the most part I'm stumped, I bought a small collection recently and have been looking through my collection from when I was really young and these are the last ones I have to identify. Please let me know if I need to take more pictures or provide more information for any of these, thank you!

These two (above and below) were both found in central Texas, specifically Whitney. both ~6.5-7 hardness




I believe this is amazonite but it looks quite a bit different from other pieces I have. ~6 hardness


Seems to be harder than 7, I can't scratch with quartz though the darker layer on the bottom seems to be weaker/softer.


Same thing, harder than 7 it seems


I've been having trouble doing the scratch test with this one but it feels very dense and noticeably heavier than other rocks the same size.


This one can be scratched by glass but not a penny so 3.5-5.5


My best guess is calcite since they can be scratched with with a penny but I haven't seen any that looks like this.


This one is 3.5-5.5 but really stumped me, definitely has crystals but they all seem to be different shapes. Was also found in Whitney, Texas.


I'm fairly sure this is epidote but I've seen similar rocks being called olivine or serpentine.

 

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[stdenis_jd]

I'll hit a few of em:

1 & 2) - possibly a limb cast, otherwise chalcedony replacement
3) blue apatite
4) some kind of picture jasper
5) chalcedony/carnelian
6) looks like rhodonite but I don't think it is. Nothing comes to mind on this one.
7) orange calcite or marble (looks like it could be metamorphosed which would make it marble)
8) calcite (test with acid)
9) the most interesting one. Looks like a psuedomorph, goethite after (? pyrite, marcasite, hematite, magnetite?)
10) quartz with feldspar alteration to epidote, some k-feldspar & quartz remaining

 

[stdenis_jd]

Addition to #6 - I'm thinking the pink is tourmaline, clear quartz, and the black must be biotite mica schist. I'm not too sure about the schist or biotite

 

[fuss]

If it were mine I would probably break off a piece of #9 to see whats going on. Nice finds, #3 has great color.

 

[DDancer]

For #6 I'm of the opinion of a quartz/garnet mix.

 

[sthaney]

Thank you so much for your help, number 9 was especially strange to me but I think it is a pseudomorph after comparing several images. It's probably either goethite or limonite but what's really throwing me off is that the crystals are mostly in plus shapes, something I've never seen before.

 

[stdenis_jd]

Thank you so much for your help, number 9 was especially strange to me but I think it is a pseudomorph after comparing several images. It's probably either goethite or limonite but what's really throwing me off is that the crystals are mostly in plus shapes, something I've never seen before.

what I'm seeing there is cubic structure and possibly pyritohedron (sort of an unorthodox dodecahedron). Could also be hexagonal from what I see in the pic but I doubt it. I'm also not exactly great at examining crystal structures so I could be wrong