Edenite

NaCa₂Mg₅(Si₇Al)O₂₂(OH)₂IMA symbol: Edredefined

Edenite is a silicate mineral with the formula NaCa2Mg5(Si7Al)O22(OH)2, crystallizing in the monoclinic system. It has a Mohs hardness of 5.5, typically black, brown or green in color, a specific gravity of 3.223. Its streak is white.

Photos

Edenite specimen photo — Robert M. Lavinsky · CC BY-SA 3.0 · Commons

Physical properties

Hardness (Mohs)	5.5single sourceWikidata (CC0)
Specific gravity	3.223 g/cm3single sourceDana's System, 2nd Appendix (1909)
Color	black, brown, greensingle sourceDana's System, 2nd Appendix (1909)
Streak	whitesingle sourceWikidata (CC0)

Chemistry (calculated)

Molecular weight	834.25 g/molcalculated from the IMA formula
Composition (wt%)	Na 2.76%, Ca 9.61%, Mg 14.57%, Si 23.57%, Al 3.23%, O 46.03%, H 0.24%

Classification

Nickel-Strunz (10th)	9.DE.15Wikidata (CC0)
Nickel-Strunz (9th)	9.DE.10Wikidata (CC0)