- a magnesium-rich mica mineral, usually yellowish-brown, but sometimes reddish-brown.
Origin of phlogopite
1840–50; < Greek phlogōp(ós) fiery-looking (phlog-, stem of phlóx flame + ōp(ḗ) view, look + -os adj. suffix) + -ite1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- a brownish mica consisting of a hydrous silicate of potassium, magnesium, and aluminium, occurring principally in metamorphic limestones and ultrabasic rocks. Formula: KMg 3 AlSi 3 O 10 (OH) 2See also mica
C19: from Greek phlogōpos of fiery appearance, from phlox flame + ōps eye
- A yellow to dark-brown mica. Phlogopite is monoclinic and is usually found in limestone. It is used in insulation. Chemical formula: K(Mg,Fe)3AlSi3O10(OH)2.
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