- a mineral, calcium aluminum iron silicate, Ca2(Al, Fe)3Si3O12(OH), occurring in green prismatic crystals.
Origin of epidote
1800–10; < French épidote < Greek *epidotós given besides, increased (verbid of epididónai), equivalent to epi- epi- + dotós given (verbid of didónai)
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for epidote
Mica, epidote, and chlorite are also present as accessories.Volcanoes: Past and Present
A rock composed of quartz and epidote is known as epidosite.
Fragments of epidote, porphyry and flinty quartzite lay around.A Report on Washington Territory
William Henry Ruffner
Quartz is not much harder than epidote; the strength is only supposed to be in some proportion to the squares of the diameters.
He lets the pale little film of epidote grow right past him; stopping his own summit for it; and he never himself grows any more.
- a green mineral consisting of hydrated calcium iron aluminium silicate in monoclinic crystalline form: common in metamorphic rocks. Formula: Ca 2 (Al,Fe) 3 (SiO 4) 3 (OH)
C19: from French épidote, ultimately from Greek epididonai to increase, from didonai to give; so called because two sides of its crystal are longer than the other two sides
- A yellowish-green or blackish-green monoclinic mineral. Epidote occurs as formless grains or as prism-shaped crystals, and is found in limestones that have undergone slight metamorphism or in igneous rocks. Chemical formula: Ca2(Al, Fe)3(SiO4)3OH.
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