Calsilica Jewelry Also called “rainbow calsilica”, calsilica is a very beautiful stone with bright rainbow bands. It is a calcite mineral newly found in Mexico. When it first appeared in public a little over a decade ago, this gem made quite a splash with its vivid and varied colors and became an instant favorite in jewelry. If you are looking for jewelry that is pretty and fun, then choose from JeGem’s high-grade calsilica pieces with vivid and colorful rainbow bands in one-of-a-kind designs available nowhere else!