Rainbow Moonstone is an orthoclase feldspar mineral. Feldspars are some of the worlds' most common minerals and include labradorite, amazonite, sunstone and albite. Though sometimes confused with labradorite; rainbow moonstone is generally white with blue,green, or red flashes sometimes all on the same stone.
Amethyst is a type of quartz in which impurities of manganese or iron have given it its purple color.
I can assemble any 2 stones together in the same ring. Please email me for inquireys about the many stones that work well on the same piece.