name that stone

Quoted text begins.A right angle fracture such as you describe is not typical for quartz
(which has a conchoidal fracture that will be visible if a large
crystal, and made up of multiple intersecting conchoidal fractures, if a
poly-crystalline lump of quartz.) What you are describing might be a
type of feldspar with cleavages close to 90 degrees. Fluorite is a
cubic mineral with right angle fractures but is not very hard.
End of quote.

Thanks for answering my thread. I'm not sure exactly
what kinds of angles these stones fracture at but I can
say that they seem like a very commonly used landscaping
device for things like edging or border thus suggesting
to me that I'm not exactly dealing with any type of
stone or mineral that could be considered as semi
precious or valuable as a raw material. However, I can
also say that since I started experimenting I can't stop
thinking about what I would like to do with it. These
are very hard and beautiful stones and although I'm used
to carving softer marbles and limestones I do have a
little experience with granite. I feel that I'll
probably be doing a lot of resharpening chisels and
using a lot of cutting with my 4-1/2" diamond blade.
I'll go home today and take a closer look at the angle
which the stone fractures and report my findings
tomorrow.

If feldspar, would these stones be commonly used in
landscaping. I'm not sure if I pointed out that these
stones, on the surface, are very smooth and white. They
appear to have been taken from a stream or river due to
the smooth roundness that seems to be the result of
water running over them for eons.

Thanks again for the response,
Anthony Marbella - Sculptor
Pittsburgh, Pa