Granite
Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase) · Decorative Stone / Industrial Mineral / Rock Specimen
Crystal System
Phaneritic (holocrystalline) texture; individual minerals within the rock belong to different systems including Monoclinic/Triclinic (Feldspars) and Trigonal (Quartz).
Mineral Group
Silicates (specifically Tectosilicates)
Chemical Formula
Complex mixture: SiO2 (Quartz) + KAlSi3O8 (Orthoclase) + NaAlSi3O8 / CaAl2Si2O8 (Plagioclase)
Formation Process
Igneous; formed by the slow crystallization of magma deep underneath the Earth's surface (plutonic formation) under high pressure and temperature.
About This Crystal
A coarse-grained plutonic rock showing a mottled appearance with pink/orange feldspar, translucent grey quartz, and dark biotite or hornblende. The surface is weathered, opaque, and shows an earthy to vitreous luster on fresh breaks.
Physical Characteristics
Color is a mix of salmon-pink, grey, and black; streak is white; no singular cleavage for the rock mass; fracture is irregular/uneven; specific gravity 2.63 to 2.75 g/cm3; non-fluorescent.
Optical Properties
Opaque in bulk; individual component minerals show variable refractive indices (Quartz ~1.54, Feldspar ~1.52). No macro-scale optical phenomena in this weathered state.
Hardness & Durability
Origin Region
Global distribution; commonly sourced from continental crust regions like the Canadian Shield, Scotland, Brazil, or the Sierra Nevada batholiths.
Hardness & Durability
Mohs hardness 6 to 7 (average); very high toughness and durability; excellent stability against chemicals and heat.
Care & Maintenance
Requires minimal care. Can be cleaned with warm soapy water and a soft brush; highly resistant to sunlight fading and most household chemicals.
Rarity & Value
Very common; value is low for rough specimens but fluctuates for polished decorative slabs or building materials; rarely treated.
Special Characteristics
Phaneritic texture (visible crystals); the pink coloration is typically due to potassium-rich orthoclase feldspar containing trace iron.
Lore & History
Historically used as a major building material for ancient Egyptian pyramids and Roman columns. In metaphysical lore, it is considered a 'grounding' stone and associated with stability and the Root Chakra.