What kind of mineral is this ?

[Salvatore]

Found in the north east of Connecticut and believe it to be soapstone but not exactly positive it is. Very dence in weight and color is like greenish beige. The size is around 5"x 5" wide.The crystal growth looks to be like squares combined together.

 

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[Eu_citzen]

I'm thinking it's a quartz-like something. Soapstone will be scratched with a knife, if memory serves.

 

[DDancer]

I have to agree. EU your correct, soap stone is soft enough that a knife will scratch it. Soap stone I've seen is usually pretty uniform or slightly layered in appearance and does not have any crystaline structure. Another possibility is that its a bit of massive feldspar. The angles and the luster suggest this to me. Hardness testing would help.

 

[Salvatore]

Thanks for the information but had one question, if it is massive felspar wouldn't it have triclinic or monoclinic crystals instead of cubic crystals.Photo of crystal formation.

 

[DDancer]

As I look at the pictures I dont see cubit formation. It looks more like monoclinic planes as there are no real 90 degree breaks. Here is something from minedat that helps me visualize what I'm seeing. Monoclinic - Minerals.net Glossary of Terms

 

[Eu_citzen]

View attachment 1433145 Thanks for the information but had one question, if it is massive felspar wouldn't it have triclinic or monoclinic crystals instead of cubic crystals.Photo of crystal formation.

The actual "flat planes" you're thinking are crystal related might be cleavage - which makes feldspar quite likely, as DD suggested.
When feldspar is massive it may not show much of the actual crystal-shape, forcing one to use other methods of identification, such as hardness tests.

 

[Salvatore]

Thanks for reply and check the link out monoclinic shape and it mentioning that all sides would be unequal in length. So measures some of the crystals on back side highlighted with arrows and got three sides 56/64 and got 48/64 on forth side of crystal. Three equal sides and one unequal?

 

[DDancer]

Monoclinic
Any mineral that falls under the following specifications belongs to the monoclinic crystal system:
Three axes, all of them are unequal in length. Two of them are at right angles to each other, while the third is lies at an angle other than 90°.

You have pretty well described a monoclinic crystal. Note two sides are at 90 deg~ parallel~ and the following sides are other than 90 deg. What is not real well pictured is the last axis but by looking at the coarseness of the plane it is something other than 90 deg as well or there would be a smooth appearance. The lengths of the apparent crystal *now I see what your focused on* are not something I consider critical but the angles of the planes that I can pick out from the photo are.
Why are they not critical? The mineral is obviously massive, ie impacted crystals, and has most likely been subjected to pressure strains that can deform crystals in the matrix. There is also the possibilities of twinning and alterations by heat that can further confuse the subject. The lines you are detailing may just be simple fractures and not the actual crystal itself.

Eu's statement in the previous post stands true in the regard of massive minerals. Hardness test, density test and an investigation to the related minerals where your specimen was found are additional clues for identifying specimens with no specific or distinct characteristics. Though I'm happy to be proven wrong

 

[Eu_citzen]

View attachment 1433214View attachment 1433215 Thanks for reply and check the link out monoclinic shape and it mentioning that all sides would be unequal in length. So measures some of the crystals on back side highlighted with arrows and got three sides 56/64 and got 48/64 on forth side of crystal. Three equal sides and one unequal?

I am well aware of the monoclinic crystal structure, thank you.
As DD said, we are here not deal with a crystal, since a crystal has "crystal faces", flat surfaces which determine the size & shape of the crystal.
The crystal "grew" into that shape. To grow, a crystal needs space, i.e. cavities in a rock.
You however have a massive piece of something.

Crystal examples: