Peridot
Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4
Category
Browse sedimentary (processed mineral product) specimens identified by the Rock Identifier community.
Peridot
Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4
Cobaltian Calcite
Cobalt-bearing Calcite (Ca,Co)CO3
Quartz (likely tumbled or naturally water-worn)
Quartz (SiO₂ - Silicon Dioxide)
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
Sandstone Chert/Quartzite
Silicon Dioxide (SiO2) - Sedimentary Sandstone / Orthoquartzite
Calamites Fossil (Horsetail Stem)
Calamites (Genus), part of the class Equisetopsida
Black Jasper
Silicon Dioxide (SiO2) with Carbonaceous inclusions
Tumbled Stones (various)
Mixed Silica-based Minerals (primarily Quartz and Chalcedony)
Pyrite
Pyrite (Iron sulfide, FeS₂)
Quartz
Quartz (SiO2)
Quartz
Quartz (Silicon Dioxide - SiO2)
Quartz with Iron Stains
Quartz (SiO2) with iron oxide/hydroxide staining
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Jasper
Jasper (Silicon Dioxide, SiO2)
Fossilized Brachiopod
Brachiopoda (Class Rhynchonellata or Spiriferida)
Jasper
Silicon dioxide (SiO2)
Jasper Pebble
Tumbled Jasper (Microcrystalline Quartz, SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert (specifically Flint or Jasper-Chert)
Silicon Dioxide (SiO2)
Yellow Jasper
Jasper (Silica-rich Microcrystalline Quartz, SiO2 with Iron impurities)
Yellow Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Agate/Flint variant)
Microcrystalline Quartz (SiO2)
Banded Iron Formation
Banded Iron Formation (BIF)
Chert / Flint (River Pebble)
Cryptocrystalline Quartz (SiO2)
Black Jasper (Black Onyx substitute)
Silicon Dioxide (SiO2) with carbonaceous impurities
White Marble
Metamorphosed Limestone (principally CaCO3)
Phyllite
Phyllite (Foliated metamorphic rock)
Chert (Arrowhead variety)
Chert (SiO2)
Greywacke (likely)
Greywacke (a type of sandstone)
Not a geological specimen
N/A (man-made object)
Fossil Shell (Bivalve)
Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)
N/A - Image does not contain a rock or mineral
Anthropogenic textile material
Blue Chalcedony and Picture Jasper Beads
Blue Chalcedony (SiO2), Picture Jasper (SiO2)
Pebble or Cobble (likely composed of sandstone or conglomerate)
Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)
Chert (specifically Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Chert (Nodular Chert)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Shale or Slate with Quartz Veins
Shale (fine-grained clastic sedimentary rock) or Slate (low-grade metamorphic rock formed from shale) with Quartz (SiO2) veins
River Rock
Sedimentary Rock (various compositions)
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite mica
Olivine (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4
Chert (Flint)
Microcrystalline Quartz (SiO2)