Spinel is aluminum and magnesium oxide with formula Al2MgO4 the MgO · Al2O3. In it, magnesium can be partially replaced by iron, zinc, manganese or cobalt, alin - by …
Diamonds Emeralds Rubies Sapphires
Spinel is aluminum and magnesium oxide with formula Al2MgO4 the MgO · Al2O3. In it, magnesium can be partially replaced by iron, zinc, manganese or cobalt, alin - by …