Spinel

Name:
Spinel
Detailed information:

M Formula:	MgAl2O4
Properties:
Color, various shades of red, grading to green, brown, and black; luster vitreous. Hardness 8. There are many varieties.
Occurrence:
New York, New Jersey, Massachusetts, Virginia, North Carolina, Ceylon, Thailand, Mozambique.
Use:
Crystallography; synthetic spinel is used as a refractory and in electronic applications.