Gneiss
Gneissic Metamorphic Rock
Category
Browse mixed: igneous and sedimentary specimens identified by the Rock Identifier community.
Gneiss
Gneissic Metamorphic Rock
Pyrite
Iron Disulfide (FeS2)
Red Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Green Calcite
Calcium Carbonate (CaCO3)
Hematite
Iron(III) oxide (Fe2O3)
Gneiss
Gneiss (high-grade metamorphic rock typically composed of quartz, feldspar, and mica)
Rough Quartz (or Quartzite pebble)
Silicon Dioxide (SiO2)
Gneiss (Metamorphic Cobble)
Gneiss (High-grade Regional Metamorphic Rock)
Banded Gneiss
Gneiss (quartz-feldspar-biotite metamorphic rock)
Bumblebee Jasper
Volcanic Tuff (mixture of Quartz, Sulfur, Hematite, and Orpiment)
Sand (Construction Grade)
Unconsolidated siliciclastic sediment (primarily SiO2)
Kaolinite (Chalky Clay)
Kaolinite (Al2Si2O5(OH)4)
Labradorite (tumbled)
Labradorite (a plagioclase feldspar mineral between anorthite and albite; chemical formula: (Ca,Na)(Si,Al)4O8)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Citrine
SiO2 (Silicon Dioxide)
Schorl (Black Tourmaline)
NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
Moonstone
Orthoclase Feldspar (KAlSi3O8) with inclusions of Albite
Black Tourmaline
Schorl (Sodium iron aluminum borosilicate), NaFe3Al6(BO3)3Si6O18(OH)4
Smoky Quartz
Silicon Dioxide (SiO2)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8)
Citrine
Silicon Dioxide (SiO2) with iron impurities
Smoky Quartz
Silicon Dioxide (SiO2)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8)
Green Aventurine (Carved)
Silicon Dioxide (Quartz variant) with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O(OH)2)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz (Tumbled)
Smoky Quartz (Silicon Dioxide - SiO2)
Blue Sapphire
Corundum (Al2O3)
Yellow Quartz / Citrine Quartz
Silicon Dioxide (SiO2)
Moonstone (Orthoclase Feldspar)
Orthoclase (KAlSi3O8) with Albite (NaAlSi3O8)
Milky Quartz with Iron Inclusions
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) - variety of Chalcedony
Sandstone Concretion
Septarian Concretion (Nodule)
Sandstone
Arenite (SiO2 based typically)
Sandstone (Yellow/Tan Sandstone)
Arenite (primarily Quartz, SiO2)
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Banded Chert
Silicon dioxide (SiO2) - Microcrystalline Quartz
Chert (River Siltstone/Quartzite type)
Microcrystalline Quartz (SiO2)
Quartz (likely Rose Quartz or Milky Quartz based on color)
Quartz (SiO2 - Silicon Dioxide)
River Rock (Basalt/Greywacke)
Aphanitic Basalt or Lithic Sandstone (Greywacke)