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Monday, January 16, 2017

TAAF 2017 - Pyroxene




COUNTRY: TAAF
ISSUE DATE: 2 January 2017
STAMP THEME: Pyroxène
STAMP SIZE: 52 x 40 mm
STAMP DESIGN: Claude Perchat


The pyroxenes (commonly abbreviated to Px) are a group of important rock-forming inosilicate minerals found in many igneous and metamorphic rocks. Pyroxenes are silicon-aluminum oxides with Ca, Na, Fe, Mg, Zn, Mn, Li substituting for Si and Al.

The name pyroxene is derived from the Ancient Greek words for fire and stranger. Pyroxenes were so named because of their presence in volcanic lavas, where they are sometimes seen as crystals embedded in volcanic glass; it was assumed they were impurities in the glass, hence the name "fire strangers".



Stamp images thanks to La Poste


La Poste