mineral
Feldspar
KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8
AI-generated identification · may be incorrectHardness of 6 on the Mohs scale with a vitreous to pearly luster. Exhibits prismatic crystal habits and prominent two-directional cleavage intersecting near 90 degrees.
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Physical properties
Hardness of 6 on the Mohs scale with a vitreous to pearly luster. Exhibits prismatic crystal habits and prominent two-directional cleavage intersecting near 90 degrees.
Formation & geological history
Forms primarily in igneous rocks like granite and pegmatites through fractional crystallization of cooling magma.
Uses & applications
Widely used in the manufacture of glass, ceramics, porcelain, and occasionally as semi-precious gemstones like moonstone.
Geological facts
Feldspar is the single most abundant mineral group in the Earth's crust, comprising approximately 41% of it.
Field identification & locations
Identified by its rectangular crystal shape, good cleavage planes, and characteristic hardness that scratches glass.
More like this
Other mineral specimens
Gneiss or Schist
Gneiss or Mica Schist with Garnet
Metamorphic
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Tumbled granite
Granite, a coarse-grained felsic intrusive igneous rock
igneous
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Granite
Granite (Phaneritic intrusive igneous rock)
igneous