The business owner is looking for something that will catch light and give a little sparkle.Thanks.
they are usually quite distinct visually. quartz is (usually) translucent and feldspar is opaque, the crystal forms are different and the coloration is different. worst comes to worst, go through the physical tests (hardness, scratch test, etc.) Although it takes a bit of experience to learn the two apart, they really are not the same in detail and are actually pretty difficult to confuse for anyone with experience.
Based on cleavage. Quartz has a conchoidal fracture (no cleavage) whereas feldspars have 2 clear planes of cleavage. Based on hardness. Quartz has a hardness of 7, therefore it cannot be scratched by steel. Based on thin section under XPL. The two are very different under crossed polars, quartz goes into anisotropic extinction every 90?. Feldspars are often twinned, elongate and regular shaped.
well it can be easy to tell them apart. quartz is usually identifiable by their grainy texture. Quartz sand grains are between 0.063mm to 2mm in diameter. It is also light coloured. Feldspar is generally deeper in colour. Feldspar crystals will be bigger than quartz crystals. hope this helps :)
