Fluorapatite on Albite

Fluorapatite – Ca₅(PO₄)₃F

Elements: Calcium, Phosphorus, Oxygen, Fluorine

Class: Phosphates

Crystal System: Monoclinic

Hardness: 5

Apatite

Talc (1)Diamond (10)

About as hard as a steel knife blade.

Albite – Na(AlSi₃O₈)

Elements: Sodium, Aluminum, Silicon, Oxygen

Class: Silicates – Tectosilicates

Crystal System: Triclinic

Hardness: 6-6.5

Orthoclase

Talc (1)Diamond (10)

Scratches glass. Harder than a steel knife.

Origin: Sapo Mine, Ferruginha, Conselheiro Pena, Doce Valley – Brazil

More minerals containing Oxygen