Light Blue Mineral with VERY low hardness

Mineral was found in Portland, Connecticut in 2002.

I tried searching, but there are just too many minerals in that area to pinpoint.


Mineral is brittle, just during the scratching process, 2 small pieces broke off.
Mineral can be scratched by Calcite (3)
Mineral can scratch my fingernail (2)

This looks like Calcite to me. Try a drop of acid on it and see if it bubbles.

Vik

blue calcite

This looks like calcite. Try the acid test described above. Slight to moderate effervescence can also be observed if a small sample of the mineral in question is finely powdered and placed in hot vinegar although muriatic acid (HCl) produces a far more obvious result upon reaction with carbonates. Like the peridot you found, I believe this specimen is most likely from a foreign location. I have not seen this habit of calcite associated with central Connecticut pegmatites. Calcite is also quite rare in felsic environments. Be careful...

Coelestine has a hardness of 3 and shows sometimes a blue colour.

Uwe Kudwig

To me, looks as calcite but could be also celestine (similar hardness, also 3 cleavage planes...).
You can check density to differentiate calcite (2,7) from celestine (3,8) in this easy way:
[www.mindat.org]

Josele

Do a flame test with one of the pieces that broke off in your scratch test. This should be conclusive enough in this case.

It is calcite! From Gouvenour NY.. I found a piece of paper deep in my closet. It only makes sense that it is this!