Diorite (possibly fine-grained variety or a related intermediate intrusive rock like a felsic gabbro or a dark granodiorite)
Diorite (Igneous rock, intrusive, intermediate composition)
Igneous Rock
Category
Mineral (Silicate Variety)
Browse mineral (silicate variety) specimens identified by the Rock Identifier community.
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Mineral
Sandstone (likely Greywacke or Siltstone variety)
Arenite / Siltstone (primarily SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Obsidian
Obsidian (Volcanic Glass)
igneous
Obsidian
Volcanic Glass (SiO2 + minor impurities)
igneous
Chert (Jasper/Agate variety)
Cryptocrystalline Quartz (SiO2)
sedimentary
Granite
Phaneritic Igneous Rock (composed primarily of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Blue Calcite
Calcium Carbonate (CaCO3)
mineral
Obsidian
Volcanic Glass (SiO2)
igneous
Chert Pebble (Jasper/Quartz variety)
Microcrystalline Quartz (SiO2)
sedimentary
Magnetite (Iron Ore)
Magnetite (Fe3O4)
mineral
Halite (Rock Salt)
Halite; NaCl (Sodium Chloride)
Mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Rose Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Granite
Granite (Phaneritic intrusion / SiO2 + KAlSi3O8 + NaAlSi3O8)
igneous
Quartz (possibly Citrine or Smoky Quartz variety)
Silicon Dioxide (SiO2)
mineral
Shell Cameo (Sardonyx Shell)
Cassis madagascariensis (Sardonyx shell)
mineral (biogenic silica/calcium carbonate substrate)
Plagioclase Feldspar (specifically Albite/Oligoclase)
(Na,Ca)(Si,Al)4O8
mineral
White Quartz
Silicon Dioxide (SiO2)
mineral
Kyanite (in Schist Matrix)
Kyanite (Al2SiO5)
metamorphic
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Mineral
Obsidian
Volcanic glass
igneous
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Granite
Phaneritic Felsic Igneous Rock
igneous
Schist
Schist (various mineral compositions)
Metamorphic
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Mineral
Blue Quartz
Quartz (SiO2) with inclusions
Mineral
Quartzite (specifically Milky Quartz variety)
Quartz (SiO2)
metamorphic
Basalt with Scoria/Vesicular Texture
Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
igneous
Botryoidal Hematite (Kidney Ore)
Hematite (Fe2O3)
Mineral
Citrine
SiO2 (Silicon Dioxide)
Mineral
Black Freshwater Pearls
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Chert / Flint (a variety of Chert)
Chert (SiO2)
Sedimentary Rock (technically a microcrystalline quartz mineral aggregate)
Chlorite (Small Flakes/Sand)
Chlorite Group (Magnesium Iron Aluminum Silicate Hydroxide - (Mg,Fe)3(Si,Al)4O10(OH)2·(Mg,Fe)3(OH)6)
mineral
Scoria
Scoria (a vesicular basalt or andesite)
igneous
Yellow Quartz (Citrine Quartz variety / Ferruginous Quartz)
Silicon Dioxide (SiO2) with iron inclusions
mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace impurities of Titanium, Manganese, or Iron
mineral
Chert (variations include Flint/Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
sedimentary
Quartz
Quartz (SiO₂)
Mineral