Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Category
Mineral, Specifically A Rock Fragment
Browse mineral, specifically a rock fragment specimens identified by the Rock Identifier community.
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Pegmatitic Granite
Granite with Orthoclase Feldspar and Quartz (SiO2, KAlSi3O8)
igneous
Basalt
Basalt (a mafic extrusive igneous rock)
Igneous
Aventurine
Silicon Dioxide (Quartz with Fuchsite inclusions) - SiO2
metamorphic
Basalt
Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)
Igneous
Orthoceras Fossil in Limestone
Orthoceras regulare (Class Cephalopoda; Order Orthocerida)
sedimentary
Sunstone
Plagioclase Feldspar (specifically Oligoclase variety containing hematite or goethite inclusions)", composition: (Ca,Na)(Al,Si)2Si2O8
Mineral
Red Jasper (Opaque Chalcedony)
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary
Marble
Metamorphosed Limestone/Dolomite
metamorphic
Peach Moonstone
Orthoclase Feldspar (KAlSi3O8)
mineral
Green Jasper (Chert)
Silicon Dioxide (SiO2)
sedimentary
Travertine (Tufa)
Calcium Carbonate (CaCO3)
sedimentary
Chert (specifically Tan/Yellow Chert)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
sedimentary
Tektite (likely Australite)
Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)
Mineral (specifically a mineraloid)
Pink Granite
Granite (Alkali-feldspar granite)
igneous
Mahogany Obsidian Arrowhead
Obsidian (volcanic glass) with Hematite inclusions
igneous
Conglomerate with Fossilized Shark Teeth
Clastic sedimentary rock (Conglomerate) containing Elasmobranchii remains
sedimentary
Amber
Succinite (specifically for Baltic amber); approximate formula C10H16O
Mineraloid
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Sunstone
Heliolite (Sodium Calcium Aluminum Silicate with Iron or Copper inclusions)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Green Quartzite (Aventurine-like)
Quartzite with Fuchsite inclusions (SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Zebra Jasper
Silicon Dioxide (SiO2) with impurities; typically a form of Chalcedony/Microcrystalline Quartz
sedimentary
Sandstone (Ferruginous)
Arenite (Iron-rich)
sedimentary
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Selenite
Gypsum (CaSO4·2H2O), specifically the crystalline variety Selenite
Mineral
Jasper Breccia
Silicon Dioxide (SiO2) - Brecciated Microcrystalline Quartz
sedimentary
Ferruginous Sandstone (Grit)
Clastic Sedimentary (Ironstone-rich Sandstone)
sedimentary
Almandine Garnet
Almandine (Fe3Al2(SiO4)3)
mineral
Greywacke (River/Beach Pebble)
Greywacke (Impure Sandstone)
sedimentary
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with impurities
sedimentary or igneous-associated mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
White Chalcedony (Agate)
Silicon Dioxide (SiO2)
mineral
Blue Calcite
Calcium Carbonate (CaCO3)
mineral
Shale or Mudstone (Based on appearance)
Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)
Sedimentary
Apache Tear
Obsidian (Hydrated Volcanic Glass)
igneous
Picture Jasper
Silicon Dioxide (SiO2) - Opaque Impure Chalcedony
sedimentary
Jasper, possibly Brecciated Jasper or Ocean Jasper due to patterns and color
Silicon Dioxide (SiO2), a variety of Chalcedony
Sedimentary Rock
Specular Hematite (Specularite)
Iron Oxide (Fe2O3)
mineral
Leopard Skin Jasper
Chalcedony (cryptocrystalline Quartz)
Mineral