Mineral on Igneous Rock
Quartz on Basalt
Silicon Dioxide (SiO2) on Mafic Igneous Rock
Hardness: 7 (quartz), 5-6 (basalt); Color: White/clear crystals on dark gray/black host rock; Luster: Vitreous to pearly crystals; Structure: Hexagonal crystals on a fine-grained crystalline matrix.
- Hardness
- 7 (quartz), 5-6 (basalt)
- Color
- White/clear crystals on dark gray/black host rock
- Luster
- Vitreous to pearly crystals
Identified More mineral on igneous rock →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 (quartz), 5-6 (basalt); Color: White/clear crystals on dark gray/black host rock; Luster: Vitreous to pearly crystals; Structure: Hexagonal crystals on a fine-grained crystalline matrix.
Formation & geological history
Formed through hydrothermal precipitation where silica-rich fluids filled cavities (vesicles) or cracks in cooling volcanic basaltic lava flows.
Uses & applications
Commonly used for geological study, teaching specimens, and minor decorative items or aquarium stone.
Geological facts
Quartz is the second most abundant mineral in Earth's continental crust. When it grows inside the gas bubbles of basalt, it can eventually form geodes if the pocket is large enough.
Field identification & locations
Identify in the field by the contrast between a dark, heavy, fine-grained rock and white, hard crystals that can scratch glass. Often found in volcanic regions.
More like this
Other mineral on igneous rock specimens
Quartz Druzy on Basalt
Silicon Dioxide (SiO2) on Mafic Volcanic Rock
Mineral on Igneous Rock
Magnetite
Magnetite (Fe3O4)
mineral
Nephrite Jade
Nephrite
Mineral/Rock
Granite with Epidote
Granite, containing quartz, feldspar, and epidote
Igneous
Dark-colored Igneous Rock (likely Basalt or Diabase)
Basalt (extrusive igneous) or Diabase (intrusive igneous)
Igneous Rock
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral