spinel /spɪˈnɛl/ noun3 •Any of several hard minerals of cubic symmetry that are mixed oxides of magnesium and aluminium and are used as gemstones of various colours. •Any crystalline material, not necessarily an oxide, that possesses the same crystal structure as this mineral. •(no longer used) Spindle; the amount of yarn that fits on a spindle.[…] raised the price of that staple of yarn (of one Spinel in the pound weight) from 23d. to 26d. per Spinel. — 1726 formsspinels
