Petrified Wood
Silicified Wood (SiO2)
mineral
Category
Organic Material (Likely A Fruit Or Berry)
Browse organic material (likely a fruit or berry) specimens identified by the Rock Identifier community.
Sandstone
Arenite (primarily SiO2 with iron oxide cementation)
sedimentary
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2) with iron oxide inclusions
mineral
Chert (Jasper)
Microcrystalline Silica (SiO2)
sedimentary
Chert (Nodule)
Chert (composition: SiO2)
sedimentary
Quartzite (River Cobble)
Quartzite (Metamorphosed Quartz Sandstone, SiO2)
metamorphic
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
sedimentary
Orthoceras Fossil Limestone
Orthoceras sp. (Calcium Carbonate, CaCO3)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
sedimentary
Shell Cameo (Sardonyx Shell)
Cassis madagascariensis (Sardonyx shell)
mineral (biogenic silica/calcium carbonate substrate)
Orthoceras Fossil Limestone
Orthoceras (extinct Cephalopod fossil) in Matrix
sedimentary
Fossiliferous Limestone (Coquina)
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Marble
Recrystallized Calcite Rock (CaCO3)
metamorphic
Bituminous Coal
Organic Sedimentary Rock (Carbon-based)
sedimentary
Pearl
Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3
mineral
Gneiss (specifically a weathered or stream-worn specimen)
Gneiss (Foliated Metamorphic Rock)
metamorphic
Septarian Nodule (Dragon Stone)
Septarian concretion (composition: CaCO3 - Calcite, Aragonite, and Siderite/Limestone)
sedimentary
Coquina / Shelly Limestone
Coquina (Biogenic Limestone)
sedimentary
Pyrite in Shaly Matrix
Iron Sulfide (FeS2)
mineral
Tahitian Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral
Granite (Dioritic or Hornblende-rich)
Phaneritic Plutonic Felsic to Intermediate Igneous Rock
igneous
Massive Quartz with Host Rock
Silicon Dioxide (SiO2)
mineral
Chert (Yellow/Tan Variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone
Arenite (composed primarily of SiO2)
sedimentary
Quartzite Cobble
Meta-quartzite (SiO2)
metamorphic
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
mineral
Mother of Pearl (Nacre)
Nacre (Aragonite/Conchiolin), CaCO3 + Organic Polymers
mineral
Sandstone (likely Navajo Sandstone)
Arenite (primarily SiO2)
sedimentary
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions (Limonite/Hematite)
mineral
Herkimer Diamond
Quartz (Silica - SiO2)
mineral
Sandstone (likely Graywacke or Lithic Sandstone)
Arenite / Wacke (SiO2 based with lithic fragments)
sedimentary
Muscovite Mica (likely on Quartz/Feldspar)
Muscovite - KAl2(AlSi3O10)(OH)2
mineral
Black Jasper
Silicon Dioxide (SiO2) with inclusions
sedimentary
Black Marble
Recrystallized Limestone (CaCO3)
metamorphic
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone (Muddy/Silty Variety)
Arenite with high silt/clay content (clastic sedimentary rock)
sedimentary
Pearl
Aragonite / Calcium Carbonate (CaCO3)
mineral
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Black Mountain Stone (Seiryu Stone)
Limestone with Calcite veins (CaCO3)
sedimentary
Anthracite Coal
Anthracite
metamorphic
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
sedimentary