Greywacke (River/Beach Pebble)
Greywacke (Impure Sandstone)
Category
Browse igneous or sedimentary (water worn) specimens identified by the Rock Identifier community.
Greywacke (River/Beach Pebble)
Greywacke (Impure Sandstone)
Zoisite with Ruby
Anyolite (Calcium aluminum hydroxy silicate with Corundum) Ca2Al3(SiO4)3(OH)
Yellow Jasper
Silicon Dioxide (SiO2) with Goethite/Iron oxide inclusions
Quartz Pebble
Silicon Dioxide (SiO2)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Quartzite pebble
Quartzite (primarily SiO2)
Milky Quartz (Water-worn pebble)
Quartz (Silicon Dioxide, SiO2)
Jasper and Quartzite mix
Silicon Dioxide (SiO2) with impurities
Quartz
Quartz (SiO₂ - Silicon Dioxide)
Basalt with Quartz/Calcite Veins
Basalt (Aphanitic Mafic Igneous Rock)
Carnelian
Carnelian (SiO2 - Silicon Dioxide with Iron Oxide impurities)
Hematite
Iron(III) oxide (Fe2O3)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
Jasper with Quartz Vein
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Jasper (Cream/Yellow variety)
Silicon Dioxide (SiO2) with impurities
Massive Cryptocrystalline Quartz (Chert/Chalcedony Pebble)
Silicon Dioxide (SiO2)
Chert (specifically Iron-stained River Cobble)
Silicon Dioxide (SiO2)
Green Banded Chert (Agate/Jasper)
Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite
Chalcedony (variations like Agate or Jasper)
Chalcedony (SiO₂ - microcrystalline quartz)
Concrete Fragment
Hardened Portland Cement Composite
Yellow Jasper
Silicon Dioxide (SiO2)
Quartz on Host Rock
Silicon Dioxide (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2 plus iron oxide impurities)
Quartzite Pebble
Metamorphic Quartz (SiO2)
Granite or Granitic Gneiss
Granitoid / Gneiss
Gneiss
Gneiss (High-grade metamorphic rock)
Milk Quartz (River Pebble)
Quartz (Silicon Dioxide, SiO2)
Chert (and Jasper blend)
Chert (Microcrystalline Quartz, SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Gneiss
Gneiss
Granite Cobble
Phaneritic Plutonic Felsic Rock
Quartz (White/Milky Pebble)
Silicon Dioxide (SiO2)
Chert (Brecciated Chert)
Silicon Dioxide (SiO2)
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Basalt with Quartz Vein and Weathering Crust
Amygdaloidal or Porphyritic Basalt
Banded Agate (River Stone)
Agate (Silicon Dioxide - SiO2)
Quartzite
Quartzite (SiO2)
Quartzite River Pebbles
Quartzite (primarily SiO2)
Quartz Pebble (Chalcedony/Agate)
Silicon Dioxide (SiO2)