Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
mineral
Category
Mineral Based Human Made Alloy
Browse mineral based human made alloy specimens identified by the Rock Identifier community.
Learn about Mineral Based Human Made Alloy in the encyclopedia
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Diamond (in jewelry setting)
Carbon (C)
mineral
Diamond (in jewelry setting)
Adamantine Carbon (C)
mineral
Carborundum
Silicon Carbide (SiC)
mineral
Chert (specifically Flint or Jasper variant)
Microcrystalline Quartz (SiO2)
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Gold Nugget
Native Gold (Au)
mineral
Chert (often called Flint or Jasper)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Gold Nugget
Native Gold (Au)
mineral
Muscovite Mica
KAl2(AlSi3O10)(OH)2
mineral
Opal
Hydrated silica (SiO2·nH2O)
mineraloid
Diorite (Gneissic)
Diorite
igneous
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Pearls
Pearl: biomineralized aragonite (CaCO₃) and conchiolin
gemstone
Sandstone (with Liesegang rings or joints)
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide cement)
sedimentary
Tumbled blue-dyed stone, likely basalt or blue aventurine
Likely fine-grained basalt (plagioclase and pyroxene), possibly coated or dyed; exact identification requires testing
igneous
Orange Tabby (Felis catus)
Felis silvestris catus (variety: Red Mackerel Tabby)
Organic/Biological specimen (Non-Mineral)
Vesicular Basalt (or Scoria)
Vesicular Basalt
igneous
Amethyst
Silicon Dioxide (SiO2)
mineral
Chert (Jasper/Flint variety)
Sedimentary silica (SiO2)
sedimentary
Chert (Jasper variety)
Silicon Dioxide (SiO2)
sedimentary
Limonite (Ironstone)
FeO(OH)·nH2O (Hydrous ferric oxides)
mineral
Chert / Flint
Chert (SiO2)
sedimentary
Goldstone
Aventurine glass
mineral (man-made glass)
Granite
Granite (a broadly defined plutonic igneous rock, often more specifically classified as quartz monzonite or granodiorite based on precise mineral percentages)
igneous
Red Sandstone
Quartz Arenite (iron-stained) / SiO2
sedimentary
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Geode (Unopened)
Quartz Geode (SiO2) / Chalcedony Concretion
mineral
Cherry Quartz
SiO2 (Silicon Dioxide with iron-rich inclusions/dye)
mineral
Strawberry Quartz
Silicon Dioxide (SiO2) with Hematite or Goethite inclusions
mineral
Concretion
Sedimentary Concretion (Ironstone / Calcite Concretion)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Chert (Smooth River Siltstone/Basalt variant)
Silicon dioxide (SiO2) / Microcrystalline Quartz
sedimentary
Chert (Nodular)
Chert (SiO2 - Microcrystalline Quartz)
sedimentary
Quartz Sandstone Pebble
Sandstone (SiO2 dominated)
sedimentary
Rose quartz beads
Quartz, silicon dioxide (SiO₂), pink variety
mineral
Limonite with Hematite
Hydrated iron(III) oxide-hydroxide with variable composition (FeO(OH)·nH2O)
mineral
Blue Quartz (Aventurine)
Silicon Dioxide (SiO2) with fibrous inclusions (commonly Dumortierite)
mineral
Precious Coral (Red Coral)
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Ocean Jasper Mushroom
Orbicular Jasper (Silicon Dioxide, SiO2 mixed with various impurities)
mineral
Fossilized oyster shell
Bivalvia; likely an oyster (Ostreidae), partly mineralized with calcite
fossil