Harmotome

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Harmotome
Harmotome-187662.jpg
Harmotome
General
Category zeolites
Formula
(repeating unit)
(Ba0.5,Ca0.5,Na,K)5Al5,Si11O32·12(H2O)

Harmotome is a mineral, one of the rarer zeolites; a hydrated barium silicate with formula: (Ba0.5,Ca0.5,Na,K)5Al5,Si11O32·12(H2O). It forms vitreous white well defined monoclinic crystals, often associated with calcite and other zeolites. It has a Mohs hardness of 4 to 5 and a specific gravity of 2.44 to 2.5.

Name and discovery[edit]

Named from the Greek words harmos (a joint) and temseis (I cut) because the pyramid divides parallel to the plane that passes through the terminal edges. It was first described in 1801 from an occurrence in the Harz Mountains, Lower Saxony, Germany.

References[edit]