Basalt with Weathering Rind
Basalt (Mafic volcanic rock)
Category
Browse organic structure (not a rock) specimens identified by the Rock Identifier community.
Basalt with Weathering Rind
Basalt (Mafic volcanic rock)
Basalt with Quartz/Quartzite Veins
Aphanitic Mafic Volcanic Rock with Siliceous Infillings
Granite Pebble
Granite (Phaneritic intrusive igneous rock)
Amber
Succinite (fossilized resin)
Petrified Wood
Silicified Wood (SiO2 permineralization)
Black Marble
Recrystallized Calcite (CaCO3)
Petrified Palm Wood
Palmoxylon
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
Chert (specifically Gray/Blue Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sandstone
Clastic Sedimentary Rock
Chert (Common Opal/Agate variety)
Microcrystalline Quartz (SiO2)
Sandstone (Iron-stained)
Arenite with Limonite/Hematite staining
Snakeskin Jasper
Microcrystalline Quartz (SiO2) with iron inclusions
Druzy Quartz on Chalcedony Matrix
Silicon Dioxide (SiO2)
Vesicular Basalt with Epidote
Vesicular Basalt (Mg, Fe)2SiO4 with Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))
Granodiorite
Phaneritic-textured Intrusive Granodiorite
Granite
Granite
Basalt Pebble
Extrusive Igneous Rock (Mafic)
Basalt
Mafic volcanic rock (primarily plagioclase, pyroxene, and olivine)
Basalt with Quartz/Calcite Veins
Aphanitic Mafic Igneous Rock (Hydrothermal Veined)
Conglomerate
Conglomerate (Detrital Sedimentary Rock)
Sandstone Pebble
Sandstone (Silicon dioxide-rich clastic sedimentary rock)
Quartz Pebble
Silicon Dioxide (SiO2)
Slate
Metamorphic Mudstone / Shale
Petrified Wood
Silicified Wood (SiO2)
Yellow Jasper
Silicon Dioxide (SiO2) with iron inclusions
Black Pearl (Tahitian or Irradiated Type)
Organic gemstone (Calcium Carbonate with Conchiolin Binding)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Amethyst
Silicon Dioxide (SiO2) with Iron impurities
Banded Sandstone
Arenite with Liesegang banding (primarily SiO2 with FeO(OH) impurities)
Basalt
Extrusive Igneous Rock
Smoky Quartz
Silicon Dioxide (SiO2)
Chert (with Calcite Veining)
Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) veins
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Chert (Jasper variation)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Basalt
Basalt
Quartz in Host Rock
Silicon Dioxide (SiO2) in Rhyolite or Granite matrix
Ocean Jasper (Orbicular Jasper)
Silicon Dioxide (SiO2) with iron and other mineral inclusions
Quartz (Druzy on Matrix)
Silicon Dioxide (SiO2)
Shale
Fissile Siliciclastic Sedimentary Rock
Quartz with Schist Inclusion
Crystalline Silicon Dioxide (SiO2) with Muscovite/Biotite Schist