Mesolite

Mesolite
Faroese Stamp FR 230
Issued: 9 June 1992

Mesolite is a tectosilicate mineral with formula Na₂Ca₂(Al₂Si₃O₁₀)₃·8H₂O. It is a member of the zeolite group and is closely related to natrolite which it also resembles in appearance. Like other zeolites, mesolite occurs as void fillings in amygdaloidal basalt.

Mesolite crystallizes in the monoclinic system and typically forms fibrous, acicular prismatic crystals or masses. Radiating sprays of needle like crystals are not uncommon. It is vitreous in luster and clear to white in color. It has a Mohs hardness of 5 to 5.5 and a low specific gravity of 2.2 to 2.4. The refractive indices are nα=1.505 nβ=1.505 nγ=1.506.

It was first described in 1816 for an occurrence in the Cyclopean Islands near Catania, Sicily.

References

From Wikipedia, the Free Encyclopedia. Original article here. Support Wikipedia by contributing or donating.
All text is available under the terms of the GNU Free Documentation License See Wikipedia Copyrights for details.