Fossil Shell
Invertebrate fossil (Mollusca)
fossil
Category
Sedimentary Rock (Altered)
Browse sedimentary rock (altered) specimens identified by the Rock Identifier community.
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Lapis Lazuli
Lapis Lazuli (Complex metamorphic rock primarily composed of Lazurite (Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2, Calcite, and Pyrite)
metamorphic
Shale
Fissile Siliciclastic Sedimentary Rock
sedimentary
Red Sandstone
Clastic Sandstone (typically Quartz-rich with Iron Oxide)
sedimentary
Soapstone
Steatite (primarily composed of Talc, Mg₃Si₄O₁₀(OH)₂)
Metamorphic Rock
Sedimentary Rock (Limestone or Siltstone pebble)
Sedimentary rock fragment
sedimentary
Porphyritic basaltic-andesite
Porphyritic intermediate volcanic rock; chiefly plagioclase and pyroxene/amphibole, with altered mafic minerals and iron oxides
igneous
Milky quartz in weathered host rock
Quartz, silicon dioxide (SiO₂), likely occurring in altered igneous or metamorphic matrix
mineral
Sedimentary Rock Fragments
Clastic Sedimentary Rock
sedimentary
Sandstone
Clastic Sedimentary Rock
sedimentary
Sandstone Grain
Clastic Sedimentary Rock Grain (SiO2 dominated)
sedimentary
Fossilized Brachiopod or Gastropod in Chert/Limestone
Phylum Brachiopoda / Mollusca
fossil
Weathered Sandstone or Siltstone
Sedimentary Rock
sedimentary
Sandstone or Limestone
Sedimentary Rock
Sedimentary
Jasper
Chalcedony (cryptocrystalline quartz), SiO2
Sedimentary
Bivalve Seashell Fossil
Class Bivalvia
fossil
Rounded greenish river pebble, likely basalt or altered volcanic rock
Probable basalt (fine-grained mafic silicate rock), possibly epidote/chlorite-altered
igneous
Sandstone
Quartz Sandstone (predominantly)
Sedimentary
Quartz-rich breccia or vein quartz with iron staining
Microcrystalline to crystalline SiO₂, likely quartz with iron oxides/hydroxides and altered host rock
igneous
Green Spot Jasper (Kiwi Jasper / Sesame Jasper)
Partially altered granitic rock rich in quartz, microcline feldspar, and tourmaline or amphibole inclusions
metamorphic
Quartz-bearing ironstone or breccia
Silicified iron-rich breccia; mainly quartz (SiO₂), iron oxides/hydroxides, and altered host rock
metamorphic
Shale
Shale (clastic sedimentary rock)
sedimentary
Shale
Shale (Lutite)
sedimentary
Shale
Fissile mudrock (composed primarily of clay minerals and quartz)
sedimentary
Shale (with Iron Staining)
Argillaceous mudstone / Shale
sedimentary
Shale (sub-type: Carbonaceous Shale)
Lutaceous Sedimentary Rock
sedimentary
Tumbled jasper or porphyritic volcanic stone
Likely altered basalt/andesite with quartz, feldspar, and iron-oxide minerals
igneous
Conglomerate (Quartz Pebble Conglomerate)
Quartz Pebble Conglomerate
sedimentary
Shale
Clastic sedimentary rock (primarily clay and silt minerals)
sedimentary
Chert (Agatized/Chalcedony variety)
Microcrystalline Quartz (SiO2)
sedimentary
Weathered rounded pebble
Likely altered granite or granitic gneiss fragment; exact identification is uncertain from the image
igneous
Fossil Assortment and Geological Specimens
Various (including Ammonoidea)
fossil
Shale
Shale (Lutite)
sedimentary
Shale (or Mudstone)
Laminose Mudrock (composition: clay minerals, quartz, and mica flakes)
sedimentary
Metaconglomerate
Metaconglomerate (Quartzite conglomerate)
metamorphic
Dalmatian Jasper
Peralkaline Quartz-Feldspar Rock with Arfvedsonite
igneous
Sedimentary Sandstone
Arenite (Sedimentary Rock)
sedimentary
Pitted Sedimentary Rock / Cupstone
Sedimentary rock with weathering pit (arenite / sandstone)
sedimentary
Sedimentary Rock with Crafts (Pet Rock)
Sedimentary rock decorated with synthetic materials
sedimentary
Shale
Sedimentary pelitic rock
sedimentary
Banded Sedimentary Rock
Sedimentary rock with Liesegang banding
sedimentary
Jade (Nephrite or Jadeite)
Nephrite: Ca2(Mg,Fe)5Si8O22(OH)2 (amphibole mineral); Jadeite: NaAlSi2O6 (pyroxene mineral)
Metamorphic Rock / Mineral