Gneiss (specifically a Granitic Gneiss specimen)
Gneiss (high-grade metamorphic rock primarily composed of Quartz, Feldspar, and Biotite/Amphibole)
metamorphic
Category
Mineral_rock
Browse mineral_rock specimens identified by the Rock Identifier community.
Learn about Mineral_rock in the encyclopedia
View all →
Mica schist
Schist (rich in Muscovite or Biotite mica)
metamorphic
Veined Pebble (likely a Quartz-Veined Pebble)
Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)
Sedimentary Rock (possibly conglomerate or breccia with a quartz vein)
White Quartz
Silicon Dioxide (SiO2)
mineral
Quartz with Iron Staining
Silicon Dioxide (SiO2)
mineral
Sandstone
Sedimentary rock composed mainly of sand-sized minerals or rock grains
sedimentary
Sandstone Concretion with Quartz Center
Sedimentary Clastic Rock (SiO2 matrix with Quartz core)
sedimentary
Dalmatian Jasper
Peralkaline Quartz-Feldspar Rock with Arfvedsonite
igneous
Mixed Gemstone Collection
SiO2 (Quartz varieties) and Biogenic CaCO3 (Nacre)
mineral
Gneiss
Metamorphic Gneiss
metamorphic
Tumbled jasper, likely picture jasper or brecciated jasper
Microcrystalline quartz (SiO₂), chiefly chalcedony with iron-oxide pigments
mineral
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Dark volcanic sand / basaltic sand
Basalt-derived lithic sand, chiefly plagioclase, pyroxene, and volcanic glass
igneous
Milky quartz (likely weathered quartzite or quartz vein fragment)
Quartz, silicon dioxide (SiO₂)
mineral
Sandstone (Red)
Arenite (primarily Quartz, SiO2, with Iron Oxide cement)
sedimentary
Pitted Sedimentary Rock / Cupstone
Sedimentary rock with weathering pit (arenite / sandstone)
sedimentary
Banded Sandstone (River Pebble)
Clastic Sedimentary Rock (SiO2 with impurities)
sedimentary
Sandstone
Arenite (SiO2 primarily)
sedimentary
Copper and Quartz beads
Native Copper (Cu) and Crystalline Quartz (SiO2)
mineral
Herkimer Diamond
Quartz (Silica - SiO2)
mineral
Native Copper
Copper (Cu)
mineral
Limonite Concretion / Ironstone
Hydrated iron(III) oxide-hydroxide, FeO(OH)·nH2O
mineral
Cleavable Calcite
Calcium Carbonate (CaCO3)
mineral
Pyrite
Iron Disulfide (FeS2)
mineral
Chrysocolla in Quartz
Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O in Quartz (SiO2)
gemstone
Shale
Laminated Mudstone (Shale)
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
gemstone
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
igneous
Sandstone
Clastic Sedimentary Rock
sedimentary
Granite
Intrusive Igneous Rock
igneous
Granite
Intrusive Igneous Rock
igneous
Granite
Intrusive Igneous Rock
igneous
Basalt Pebble
Extrusive Igneous Rock
igneous
Granite
Intrusive Igneous Rock
igneous
Moonstone
Orthoclase (Potassium Aluminum Silicate), Formula: (K,Na)AlSi3O8
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Quartz on Matrix
Silicon Dioxide (SiO2)
mineral
Lake Superior Agate
Chalcedony (Silicon Dioxide, SiO2) with Iron impurities
mineral
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Milky quartz-rich rock
Quartz (silicon dioxide, SiO₂), likely with mica or feldspar inclusions
mineral