igneous
Tumbled orbicular granite
Granite, predominantly potassium feldspar, plagioclase, quartz, and biotite/hornblende
AI-generated identification · may be incorrectCoarse-grained, pink-orange and white with black mafic minerals; vitreous to dull luster, interlocking crystals, no cleavage as a rock. Typical hardness is about 6–7 Mohs and specific gravity 2.6–2.8.
Identified More igneous →
Explore Tumbled orbicular granite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Coarse-grained, pink-orange and white with black mafic minerals; vitreous to dull luster, interlocking crystals, no cleavage as a rock. Typical hardness is about 6–7 Mohs and specific gravity 2.6–2.8.
Formation & geological history
Slow cooling of silica-rich magma deep in Earth’s crust produced the granite; its exact geologic age depends on locality, commonly Precambrian to Mesozoic. The rounded shape and polish are human-made through tumbling.
Uses & applications
Used as a decorative stone, cabochon, paperweight, and collector specimen; related granite is widely used for countertops, monuments, and construction aggregate.
Geological facts
The orange-pink areas are feldspar, gray translucent patches are quartz, and black grains are biotite or amphibole. The pattern may be marketed as “orbicular granite,” though true orbicules require distinctive rounded mineral structures.
Field identification & locations
Identify it by coarse interlocking pink feldspar, gray quartz, and black flakes or crystals; it will not fizz with dilute acid and is much harder than calcite. Common sources include India, Madagascar, Brazil, and Scandinavia.
