Granite
Plutonic Igneous Rock (Granite) · Mineral Specimen / Decorative Stone / Building Material
Crystal System
Multicrystalline aggregate containing various crystal systems (Trigonal, Monoclinic, Triclinic)
Mineral Group
Silicates
Chemical Formula
Complex silicate mixture containing primarily SiO2 (Quartz), KAlSi3O8 (Alkali Feldspar), NaAlSi3O8 (Plagioclase Feldspar), and K(Fe,Mg)3AlSi3O10(OH)2 (Biotite)
Formation Process
Igneous intrusion formed by the slow crystallization of magma far beneath the Earth's surface
About This Crystal
A coarse-grained intrusive igneous rock characterized by a phaneritic texture. Displays a mottled pinkish-brown and dark grey/black appearance due to the intergrowth of quartz, pink or white feldspar, and dark biotite mica flakes, giving it a speckled surface texture.
Physical Characteristics
Color ranges from pink to grey with black speckles; white streak; no single cleavage for the rock as a whole but individual mineral components exhibit distinct cleavages; uneven to subconchoidal fracture; specific gravity around 2.65 to 2.75; hard and brittle tenacity.
Optical Properties
Varies by constituent mineral grains; quartz is transparent to translucent with vitreous luster, feldspars show pearly to vitreous luster and possible twinning, biotite exhibits strong cleavage and reflection.
Hardness & Durability
Origin Region
Found globally in continental crust; major producers include Brazil, India, China, and the United States
Hardness & Durability
Mohs hardness ranges from 6 to 7 based on constituent minerals (quartz and feldspar); high toughness and durability; excellent weather resistance and stability under normal environmental conditions.
Care & Maintenance
Clean with mild soap and warm water; avoid harsh chemical cleaners or acids; very durable and resistant to scratching under normal usage.
Rarity & Value
Very common globally; value is determined by slab size, aesthetic color patterns, and polish quality for decorative or architectural applications rather than high gemstone rarity.
Special Characteristics
Composed of an interlocked mosaic of multiple distinct mineral grains, sometimes containing pegmatitic zones, graphic granite textures, or xenolith inclusions.
Lore & History
Historically used extensively in ancient architecture, sculpture, and monumental construction due to its immense strength and durability. In metaphysical practices, granite is traditionally associated with grounding, stability, strength, and balancing emotional energies.