Druzy Quartz on Chert/Siltstone
Silicon Dioxide (SiO2) on Microcrystalline Silica/Siltstone matrix
sedimentary
Category
Rock
Browse rock specimens identified by the Rock Identifier community.
Pebble (likely Sandstone or Granitic Pebble)
Clastic Sediment (or specific rock type, e.g., Arenite, Granitoid Pebble)
Rock (likely Sedimentary)
Orange Quartz (or Carnelian Chalcedony)
Silicon Dioxide (SiO2)
mineral
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Sandstone (River Cobble)
Sandstone (principally composed of Quartz, SiO2)
sedimentary
Quartz Pebble (Feldspathic / Chert Pebble)
Silicon Dioxide (SiO2) / Potassium Feldspar (KAlSi3O8)
sedimentary
River-worn Chert
Microcrystalline Quartz (SiO2)
sedimentary
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Banded Greywacke
Greywacke (Lithic wacke)
sedimentary
Dyed Quartzite
Metamorphosed Quartz (SiO2) with synthetic pigment
metamorphic
Granite
Plutonic felsic rock (Quartz, Feldspar, Mica)
igneous
Basalt
Extrusive mafic igneous rock
igneous
Slate
Foliated Metamorphic Rock (Mainly composed of Quartz, Illite, Chlorite)
metamorphic
Yellow Agate (Banded Chalcedony)
Silicon Dioxide (SiO2)
sedimentary
River Rocks (Black)
Various lithologies (e.g., basalt, chert, obsidian for black varieties), mechanically rounded clasts
Sedimentary
Quartzite with Feldspar and Mica (Granitic Gneiss Pebble)
Metamorphic Rock / Quartzite / Granitic Gneiss
metamorphic
Sandstone Pebble
Sandstone (Silicon dioxide-rich clastic sedimentary rock)
sedimentary
Vesicular Basalt (Scoria)
Aphanitic Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
igneous
Sandstone (Weathered Cobble)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Pumice and Scoria
Vesicular Volcanic Rock (Pumice: Silicic / Scoria: Mafic)
igneous
Basalt
Basalt (composition predominately Plagioclase feldspar and Pyroxene)
igneous
Dalmatian Stone
Aplite (often incorrectly called Dalmatian Jasper)
igneous
Serpentine
Antigorite/Lizardite/Chrysotile group, Mg3Si2O5(OH)4
metamorphic
Pink Granite
Phaneritic Felsic Igneous Rock (composed primarily of Quartz and Potassium Feldspar)
igneous
Basalt
Basalt (Mafic Extrusive)
igneous
Herkimer Diamond
Quartz (Silica - SiO2)
mineral
Slickenside
Tectonic Fault Scarp Surface
metamorphic
Vuggy Quartz on Matrix
Crystalline Silicon Dioxide (SiO2)
mineral
Quartz Vein in Host Rock
Hydrothermal Quartz (SiO2) in Slates/Schists
metamorphic
Quartz Vein in Gneiss or Basalt
Milky Quartz (SiO2) within Metamorphic Host Rock
Metamorphic or Igneous with Mineral Inclusion
Basalt (Greenstone/Water-worn Pebble)
Basalt (containing Chlorite/Epidote)
igneous
Hag Stone (Adder Stone / Geode-bearing Pebble)
Sedimentary Rock with Cavity (often Quartzite, Limestone, or Sandstone)
sedimentary
Sandstone (with potentially high Feldspar/Arkose content)
Clastic sedimentary rock (SiO2 dominated)
sedimentary
Druzy Quartz on Matrix
Silicon Dioxide (SiO2)
mineral
Vesicular Basalt (Lava Rock)
Basalt (Vesicular Variety)
igneous
Painted Sandstone
Sandstone (clastic sedimentary rock) with acrylic/artistic coating
sedimentary
Coal
Coal (Sedimentary Rock / Organic Rock)
sedimentary
Granite
Intrusive Igneous Rock
igneous
River Cobble (Weathered Granitoid)
Granodiorite / Quartz Diorite
igneous
Shale with Quartz Veins
Fissile Sedimentary Rock (SiO2)
sedimentary
Basalt
Extrusive mafic igneous rock
igneous
Breciated Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary