Mineral Factbook

Prehnite

Ca2Al(Si3Al)O10(OH)2IMA symbol: Prhgrandfathered

Prehnite is a silicate mineral with the formula Ca2Al(Si3Al)O10(OH)2, crystallizing in the orthorhombic system. It has a calculated density of 2.919 g/cm3.

Photos

Prehnite specimen photo
Kora27 · CC BY-SA 4.0 · Commons
Prehnite specimen photo
CarlesMillan · CC BY-SA 3.0 · Commons
Prehnite specimen photo
Mike Beauregard from Canada · CC BY 2.0 · Commons
Prehnite specimen photo
Robert M. Lavinsky · CC BY-SA 3.0 · Commons

Crystallography

Crystal systemorthorhombic crystal systemWikidata (CC0)
Space groupP 2 c m
Cell (Å, °)a = 4.646, b = 5.491, c = 18.52; α = 90, β = 90, γ = 90
Cell volume472.467 ų, Z = 2
Axial ratios0.8461:1:3.3728calculated from COD 9005043
Source structureCOD 9005043 (European Journal of Mineralogy, 1990) — 1 of 13 structures

Physical properties

Density (calculated)2.919 g/cm³calculated from COD 9005043

Chemistry (calculated)

Molecular weight412.38 g/molcalculated from the IMA formula
Composition (wt%)Ca 19.44%, Al 13.09%, Si 20.43%, O 46.56%, H 0.49%

Classification

Nickel-Strunz (10th)9.DP.20Wikidata (CC0)
Nickel-Strunz (9th)9.DP.20Wikidata (CC0)
Dana (8th)72.1.3.1Wikidata (CC0)