GIA's Gübelin Gem Project: Spinel

Spinel Colors
Photo by Robert Weldon/GIA, courtesy Dr. E. J. Gübelin Collection
GIA Collection 34618, 34661, 34662, 34908

Found in nearly every color – most notably red, pink and blue – spinels are popular gemstones because of their abundance, moderate cost and attractiveness. Red spinel has often been mistaken for ruby. Some spinel exhibits asterism (a star-shaped pattern of reflections), chatoyancy (a “cat’s-eye” effect seen in reflected light) or a color change when viewed alternately under incandescent and fluorescent lighting.