22198 - Beautiful Yellow Green Apatite Crystal - Imilchil (Morocco) Reptile Teeth Jewelry Erythrite and annabergite (Ni3(AsO4)2·8H2O) (nickel

Erythrite and annabergite (Ni3(AsO4)2·8H2O) (nickel arsenate) form a complete series with the general formula (Co

This is an impressive and unusual piece

Infundibuloceras

terrestrial (1)

and Bardet

22198 - Beautiful Yellow Green Apatite Crystal - Imilchil (Morocco) Reptile Teeth Jewelry Erythrite and annabergite (Ni3(AsO4)2·8H2O) (nickelApatite is a group of phosphate minerals, usually referring to hydroxylapatite, fluorapatite and chlorapatite, with high concentrations of OH, F and Cl ions, respectively, in the crystal. The formula of the admixture of the three most common endmembers is written as Ca10(PO4)6(OH,F,Cl)2.