mineral
Quartz with Feldspar and Matrix
Silicon Dioxide (SiO2) with Potassium/Plagioclase Feldspar
AI-generated identification · may be incorrectHardness: 7 on the Mohs scale for quartz (6-6.5 for feldspar). Color: White, clear, and pale greenish-tan with earthy brown weathered patches. Luster: Vitreous to greasy on fresh crystal faces, dull on weathered surfaces. Crystal structure: Trigonal (quartz) and triclinic/monoclinic (feldspar).…
- Hardness
- 7 on the Mohs scale for quartz (6-6
Identified More mineral →
Explore Quartz with Feldspar and Matrix in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 on the Mohs scale for quartz (6-6.5 for feldspar). Color: White, clear, and pale greenish-tan with earthy brown weathered patches. Luster: Vitreous to greasy on fresh crystal faces, dull on weathered surfaces. Crystal structure: Trigonal (quartz) and triclinic/monoclinic (feldspar). Cleavage: None for quartz (conchoidal fracture), distinct cleavage in two directions for feldspar. Specific gravity: ~2.65
Formation & geological history
Formed typically in pegmatites, hydrothermal veins, or granitic intrusive environments through the cooling and crystallization of silica-rich magmas and hydrothermal fluids over millions of years.
Uses & applications
Used in electronics, glassware, precision instruments, countertops, and as mineral specimens for geological collections.
Geological facts
Quartz is one of the most abundant minerals in the Earth's continental crust. Pegmatite specimens often host large, well-formed crystals of quartz alongside feldspar and micas.
Field identification & locations
Commonly found in pegmatite dikes, granite outcroppings, and alluvial gravels worldwide. The provided location (near central Montana) is well-known for its rich mountain ranges containing granite intrusions, pegmatites, and quartz veins, making this a geologically plausible specimen for the area.
