Rough Amethyst
Silicon Dioxide (SiO2) with Iron impurities
Category
Browse mineral in igneous rock specimens identified by the Rock Identifier community.
Rough Amethyst
Silicon Dioxide (SiO2) with Iron impurities
Feldspar (specifically Orthoclase)
Potassium Aluminum Silicate (KAlSi3O8)
Agate
Silicon Dioxide (SiO2) - Chalcedony variant
White Agate (Chalcedony)
Silicon Dioxide (SiO2)
Porphyritic Andesite
Andesite (Intermediate Extrusive Volcanic Rock)
Pink Granite
Phaneritic Felsic Intrusive Igneous Rock
Granite (specifically Brown Granite Countertop)
Phaneritic Felsic Igneous Rock (Granite-Gabbro series)
Quartz / Quartzite
Silicon Dioxide (SiO2)
Bull Quartz
Quartz (Silicon Dioxide, SiO2)
Basalt with Plagioclase Phenocrysts
Porphyritic Basalt
Diorite
Phaneritic Intrusive Igneous Rock (Intermediate Composition)
Quartz (specifically Milky or Clear Quartz)
Silicon Dioxide (SiO2)
Gneiss
High-grade metamorphic rock (Gneiss)
Milky Quartz (among River Rock)
Quartz (Silicon Dioxide, SiO2)
Basalt and Quartz Pebble
Basalt (Igneous) and Quartzite/Quartz (SiO2) pebble
Prehnite
Prehnite Ca2Al2Si3O10(OH)2
Granite
Granite
Porphyritic Rhyolite (Birdseye Rhyolite)
Rhyolite (Porphyritic texture)
Orange Calcite point
Calcite (Calcium Carbonate, CaCO3)
Quartz (Iron-stained or Rose variant)
Silicon Dioxide (SiO2)
Granite Pebble
Felsic Intrusive Igneous Rock (composed of Quartz, Feldspar, and Mica)
Granite
Phaneritic Plutonic Felsic Rock (major components: SiO2 and Al2O3)
Lapis Lazuli
Na8(Al6Si6O24)S2 (composed primarily of Lazurite, Calcite, and Pyrite)
Blue Sapphire
Corundum (Al2O3 - Aluminum Oxide with Iron and Titanium impurities)
Muscovite Mica
Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2
Granitic Pegmatite Intrusion in Host Rock
Pegmatite dike in amphibolite or schist
Quartz Pebble (with Mica or Iron staining)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Pink Granite
Felsic intrusive igneous rock (composition: SiO2 and Al2O3)
Gneiss (specifically a weathered Amphibolite or Garnet Gneiss)
Gneiss (complex silicate composition)
Granite Gneiss
Felsic Gneiss
Granite Pebble
Igneous Intrusive Rock (Quartz-Feldspar-Mica Phenocrysts)
Diorite
Plutonic Igneous Rock (Intermediate Composition)
Aventurine
Silicon Dioxide (SiO2) with inclusions
Granite
Granite
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Banded Chalcedony (Agate)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Amygdaloidal Basalt
Amygdaloidal Basalt (extrusive volcanic rock with mineral inclusions)
Quartz (specifically Milky/Gray Quartz)
Silicon Dioxide (SiO2)
Larimar
Pectolite [NaCa2Si3O8(OH)] with copper substitution
Slag (Industrial Byproduct)
Artificial silicate/iron byproduct
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)