mineral
Banded feldspar (likely plagioclase)
Plagioclase feldspar, a sodium–calcium aluminosilicate series: (Na,Ca)(Al,Si)₄O₈
AI-generated identification · may be incorrectCream to pale yellow, nonmetallic vitreous-to-pearly luster, blocky cleavage and parallel internal bands or striations; hardness 6–6.5 Mohs, triclinic crystals. The photo alone cannot confirm the exact feldspar species.
Identified More mineral →
Explore Banded feldspar (likely plagioclase) in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Cream to pale yellow, nonmetallic vitreous-to-pearly luster, blocky cleavage and parallel internal bands or striations; hardness 6–6.5 Mohs, triclinic crystals. The photo alone cannot confirm the exact feldspar species.
Formation & geological history
Crystallizes from cooling magma in igneous rocks; feldspar is abundant in Earth’s crust and occurs in rocks of many geological ages. The visible bands may reflect twinning or compositional zoning.
Uses & applications
Feldspar is widely used in glass and ceramics; attractive specimens are collected or occasionally cut as ornamental material.
Geological facts
Plagioclase commonly shows fine parallel striations on cleavage faces, a useful clue distinguishing it from potassium feldspar.
Field identification & locations
Look for hardness near 6, two cleavage directions close to 90°, and fine parallel lines; common in igneous rocks worldwide. A fresh-face scratch or laboratory analysis can confirm identification.
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
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Granite
Granite (Phaneritic intrusive igneous rock)
igneous
Septarian Pebble
Septarian nodule / Concretion
sedimentary