Granite
Phaneritic plutonic rock (Quartz, Feldspar, Mica)
Category
Browse mineraloid (man made glass) specimens identified by the Rock Identifier community.
Granite
Phaneritic plutonic rock (Quartz, Feldspar, Mica)
Sandstone
Arenite
Basalt
Basalt (containing plagioclase, pyroxene, and olivine)
Tumbled epidote-bearing rock (likely epidote–quartz–feldspar aggregate)
Epidote-rich metamorphic rock; minerals likely epidote (Ca₂(Al,Fe)₃Si₃O₁₂(OH), quartz, feldspar, and dark amphibole/biotite)
Crushed Stone / Gravel
Aggregatus saxum (variable mineral composition)
Coquina and Oyster Fossil Rock
Coquina limestone (Calcium Carbonate, CaCO3) containing fossilized Crassostrea / bivalve shells
Limestone
Sedimentary Rock (Primarily CaCO3)
Mother of Pearl (Nacre) / Shell Fragment
Biogenic Calcium Carbonate (Aragonite and Conchiolin)
Red Sandstone
Arenite (Iron-rich)
Sand Tiger Shark Tooth (Fossil)
Carcharias taurus (fossilized dentin/enameloid)
Nephrite Jade
Ca2(Mg,Fe)5Si8O22(OH)2
Crinoid Columnal Fossil in Chert
Crinoidea stemming section in Microcrystalline Quartz (SiO2)
Diabase (Dolerite)
Diabase or Dolerite
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8) with Albite inclusions
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Diorite
Phaneritic Intrusive Igneous Rock (composed of Plagioclase feldspar, Hornblende, and Biotite)
Chert (and/or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (variations include Flint/Jasper)
Cryptocrystalline Quartz (SiO2)
Diamond
Diamond (pure Carbon, C)
Silver (Jewelry form)
Native Silver (Ag)
Breccia
Breccia
Sandstone
Arenite (composed primarily of Quartz: SiO2)
Diorite
Diorite (Plagioclase feldspar and amphibole/biotite)
Greenstone
Metamorphic mafic rock (chlorite-actinolite-epidote schist)
Sandstone
Sandstone (composed predominantly of Quartz, SiO2, with Feldspar and Clay minerals)
Malachite
Malachite (Cu2CO3(OH)2)
Swirled Agate Bead
Silicon Dioxide (SiO2)
Marble
Metamorphic Limestone (CaCO3)
Rough Diamond
Diamond (pure Carbon, C)
Natural Pearl (appearing in a jewelry setting)
Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin
Amethyst (Tumbled Cabinet Stone)
Silicon Dioxide (SiO2) with iron impurities
Pink Granite
Intrusive Igneous Rock (high K-feldspar content)
Diorite
Diorite (Intermediate intrusive igneous rock)
Chert
Cryptocrystalline Quartz (SiO2)
Diamond
Native Carbon (C)
Chert (Nodule)
Chert (Silicon Dioxide, SiO2)
Granite
Phaneritic Felsic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Coquina (Fossiliferous Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
Blue calcite sphere
Calcite (CaCO₃), commonly blue-calcite variety
Sandstone (Pebble)
Arenite