Tektite (Indochinite)
Tektite (High-silica natural glass)
igneous
Category
Man Made Object (Metalwork)
Browse man made object (metalwork) specimens identified by the Rock Identifier community.
Limestone (Porous/Travertine variant)
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Chert (variant Flint/Jasper)
Microcrystalline Opaline Silica (SiO2)
sedimentary
Blue Lace Agate
Cryptocrystalline Quartz (SiO2) with trace minerals
sedimentary
Basalt (Vesicular/Amygdaloidal or Water-Worn)
Basalt
igneous
Oyster Shell (Aragonite/Calcite)
Calcium Carbonate (CaCO3)
sedimentary
Basalt
Basalt (Mafic Extrusive Igneous Rock)
igneous
Granite
Granite (Phaneritic intrusive igneous rock; primarily SiO2 and Al2O3)
igneous
Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica/Amphibole)
metamorphic
Gneiss (specifically Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Biotite/Amphibole)
metamorphic
Quartz
Quartz (Silicon Dioxide - SiO2)
Mineral
Sandstone
Sandstone (Clastic Sedimentary Rock)
Sedimentary Rock
Chert (Tan/Grey variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Quartz (likely a weathered/tumbled piece)
Quartz (SiO₂)
Mineral
Cobaltoan Calcite / Pink Dolomite (Possible)
Cobaltoan Calcite: (Ca,Co)CO3; Pink Dolomite (or Thulite): CaMg(CO3)2 or Mn-Dolomite / (Thulite: Mn2+3Al2(Si2O7)(SiO4)O(OH))
Mineral / Rock (depending on purity)
Favosites (Honeycomb Coral Fossil)
Favosites (Genus of extinct tabulate coral)
sedimentary
Red Jasper
Jasper (a variety of Chalcedony, SiO₂ with iron oxide inclusions)
Mineral
Shale (possibly)
Shale (fine-grained clastic sedimentary rock)
sedimentary
Garnet Schist
Almandine-Muscovite Schist
metamorphic
Pyrite
Pyrite (Iron sulfide, FeS₂)
mineral
Travertine (often colloquially called Tufa)
Chemical Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Granite
Granite (composed primarily of Quartz SiO2, Alkali Feldspar KAlSi3O8, and Plagioclase Feldspar)
igneous
Vesicular Basalt (Scoria)
Extrusive Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
igneous
Amber
Succinite
mineral
Mica Schist
Foliated Metamorphic Rock (rich in Muscovite or Biotite)
metamorphic
Fossilized Bone Fragment
Permineralized Vertebrate Bone (Hydrox yapatite replaced by Silica or Calcite)
sedimentary
Greenschist (Greenstone)
Greenschist (Metamorphic rock containing chlorite, actinolite, and epidote)
metamorphic
Red Jasper (possibly Red Coral or dyed Howlite)
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Quartz (vein quartz)
SiO2 (Silicon Dioxide)
Mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Quartzite
Quartzite (primarily SiO2)
metamorphic
Jasper, possibly Brecciated Jasper or Ocean Jasper due to patterns and color
Silicon Dioxide (SiO2), a variety of Chalcedony
Sedimentary Rock
Iron Meteorite
Siderite (Fe, Ni)
igneous
Banded Calcite (often marketed as Caribbean Calcite)
Calcium Carbonate (CaCO3) + Aragonite
sedimentary
Granite
Phaneritic Felsic Igneous Rock (Main minerals: SiO2, KAlSi3O8, NaAlSi3O8)
igneous
Mica Schist
Mica Schist (Main mineral constituents: Muscovite/Biotite, Quartz, Feldspar)
metamorphic
Popcorn
Zea mays everta (P. Wilson) (Botanical name for the corn variety)
Organic/Biogenic
Sandstone (River Pebble)
Arenite (SiO2 based)
sedimentary
Basalt with Vesicles
Vesicular Basalt
igneous
Anthracite Coal
Anthracite
sedimentary
Caliche (also known as hardpan, calcrete, kankar)
Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.
Mineral
Quartz Geode
Silicon Dioxide (SiO2) in Geode form
sedimentary