4.15 Carats Cushion Cut Natural Spinel Gemstone

Spinel ( /spɪˈnɛl/) is the magnesium aluminium member of the larger spinel group of minerals. It has the formula MgAl₂O₄ in the cubic crystal system. Its name comes from Latin “spina” (arrow).^[1]

Though spinels are often referred to as rubies, as in the Black Prince Ruby, the ruby is not a spinel. Balas ruby is an old name for a rose-tinted variety of spinel.