... divided into many forms, such as aluminum spinel, iron spinel, zinc spinel, manganese spinel, chrome spinel and so on. Due to the different ... , brown, and the colorless; zinc spinel is dark green and iron spinel is Black, etc. Spinel shows a hard glassy octahedral, granular ... Now people have could produce more than 200 varieties of spinel.Spinel is a family mineral, formed by contact metamorphism in ...