rhinestone

A colorless artificial gem of paste or glass, often with facets that sparkle in imitation of a diamond.

An imitation stone made of paste or strass (a lead glass), generally cut in the form of a brilliant and made and cut to imitate the diamond, set usually in silver or other inexpensive mounting. Rhinestones were extensively worn in the latter part of the eighteenth century, and are now much used in shoebuckles, clasps, and ornaments for the hair.

A colorless stone of high luster, made of paste. It is much used as an inexpensive ornament.

an artificial diamond

made of or encrusted with rhinestones

an imitation diamond made from rock crystal or glass or paste