Sandstone (with potential iron-oxide staining)
Arenite (primarily SiO2)
Category
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
Sandstone (with potential iron-oxide staining)
Arenite (primarily SiO2)
Pearl
Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
Asphalt (Bituminous Concrete)
Asphaltum / Bitumen-Aggregate Matrix
Fossilized Crab Carapace (Concretion)
Decapoda (fossil), typically preserved in calcite or siderite concretion
Moqui Marbles
Iron Oxide Concretion (Hematite/Goethite)
Clear Quartz
Silicon Dioxide (SiO2)
Asphalt (Road Aggregate)
Asphalt concrete / Bituminous mixture
Red Garnet
Almandine and Pyrope (Silicate minerals: Fe3Al2(SiO4)3 and Mg3Al2(SiO4)3)
Basalt with Quartz/Calcite Inclusions
Mafic Volcanic Rock (Fe-Mg silicate rich)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Amber
Succinite (with formula approximately C10H16O)
Sandstone (likely Arkosic or Lithic Sandstone)
Arenite (SiO2 based with mineral inclusions)
Tufa (Limestone)
Calcareous Tufa (CaCO3)
Amber Inlay Jewelry
Fossilized Resin (C10H16O)
Epidote in Matrix
Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily Quartz, SiO2)
Sandstone (Ferruginous)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
Picasso Stone
Metamorphosed Calcium Carbonate (Limestone)
Sandstone (Weathered Pebble)
Arenite (SiO2 primarily)
Baroque Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin)
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Chert (Flint variety)
Microcrystalline context of Quartz (SiO2)
Blue Tiger's Eye
Riebeckite (crocidolite variety)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Jasper)
Microcrystalline Silica (SiO2)
Moonstone
Orthoclase (Potassium Aluminum Silicate), Formula: (K,Na)AlSi3O8
Olivine (Peridot when gem-quality)
Olivine Group (Magnesium Iron Silicate, (Mg,Fe)2SiO4)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with Iron Oxide inclusions)
Diamond
Native Carbon (C)
Sandstone
Arenite (primarily SiO2)
Chrysocolla
Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)
Amber
Succinite (specifically for Baltic amber); C10H16O (Variable organic compound)
Sandstone (Quartzose Sandstone)
Clastic Sedimentary Rock (Lithic arenite / Quartz arenite)
Dendritic Agate / Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions
Gold (Elemental Metal)
Gold (Au)
Pearl
Calcium Carbonate (primarily Aragonite and Calcite), CaCO3
Pearl (Biogenic Mineral)
Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3
Drupa Quartz (Sparkly Drusy Quartz on Matrix)
Crystalline Silicon Dioxide (SiO2) on host rock
Jasper
Silicon Dioxide (SiO2) with iron and magnesium inclusions