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Identity HelpPowellite in Basalt?

8th Nov 2019 03:26 UTCRobert Darabos

05696180015731833175025.jpg
Basalt found near the outskirts of Antigua, Guatemala.  
For some reason, I have always thought the white material in the matrix was Andesine.  Tonight it randomly clicked that it is way too soft for that.  It is easily scratched by a steel knife.  It can break apart from a fingernail, but unsure if it is brittle or is scratching away.  It also has a light yellow to white reaction to LW UV light.  Some of the material is a pearly luster, though I am unable to capture it in a photograph.  It does not noticeably react with HCL.  

Could this be Powellite?  Seems to have a ton of similarities in common.  Or can another mineral (like Andesine) break down into a much softer material?  A close up image in next post.


8th Nov 2019 03:27 UTCRobert Darabos

07564970015731836671037.jpg
a close up of a couple of the crystals

8th Nov 2019 05:27 UTCD Mike Reinke

Robert, you don't expect it's just some clay mineral? They can come very glossy, and a wide range of forms.

8th Nov 2019 21:08 UTCRobert Darabos

of course, just could be clay minerals as well.  i've personally never seen pearly luster clay minerals that fluoresce, but I'm sure its pretty common
 
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