Grey Quartzite Pebble
Quartzite (primarily SiO2 - Silicon Dioxide)
Category
Browse igneous or sedimentary (water worn) specimens identified by the Rock Identifier community.
Grey Quartzite Pebble
Quartzite (primarily SiO2 - Silicon Dioxide)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Jasper (Red/Green Brecciated)
Silicon Dioxide (SiO2) with iron oxide and chlorite inclusions
River Pebbles and Quartz
Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)
Banded Gneiss
Gneiss (Metamorphic Rock)
Sandstone (with differential weathering)
Arenite / Quartz Sandstone (SiO2)
Quartzite (River-worn Shiner)
Quartzite (Formula: SiO2)
Chert (Jasper variation)
Chert (SiO2)
Basalt with Quartz Veining
Basalt (Mafic Volcanic Rock with SiO2)
White Agate (Chalcedony)
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Cryptocrystalline quartz (SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt (containing secondary minerals like Quartz, Zeolites, or Calcite)
Basalt
Basalt (Mafic volcanic rock)
Basalt
Basalt (Mafic volcanic rock)
Gneiss Pebble
Gneiss
Quartz (Milky/Gravel variety)
Silicon Dioxide (SiO2)
Carnelian
Cryptocrystalline Quartz (SiO2 with iron oxide impurities)
Chert (and Quartz Gravel)
Chert (Cryptocrystalline Quartz, SiO2)
River Cobble (likely Sandstone or Siltstone type)
Sandstone or Siltstone (common rock types that form river cobbles)
Hematite (Iron Ore)
Hematite (Fe2O3)
Almandine Garnet
Iron aluminum silicate (Fe3Al2(SiO4)3)
Blue-dyed Quartz Druzy
Silicon Dioxide (SiO2) with artificial pigment
Amethyst
Amethyst (SiO2 - Silicon Dioxide with iron impurities)
Gneiss
Gneiss
Pyrite
Iron Pyrite (FeS₂)
Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica/Amphibole)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Red Chert / Jasper nodule)
Silicon dioxide (SiO2)
Milky Quartz
Quartz (Silica / Silicon Dioxide), SiO2
Jasper Conglomerate (Puddingstone)
Siliceous Conglomerate (Quartz and Jasper clasts in a fine-grained matrix)
Milky Quartz (Water-Worn Pebble)
Quartz (Silicon Dioxide, SiO2)
Pumice
Pumice (a highly vesicular volcanic rock)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Red Jasper
Silicon dioxide (SiO2) with iron oxide impurities
Ferruginous Quartz (Iron-stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions (Limonite/Hematite)
Chert (containing Flint and Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint Pebble)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
Hematite
Iron (III) Oxide (Fe2O3)
Gneiss (specifically a Granitic Gneiss)
Gneiss (typically composed of Quartz, Feldspar, and Mica/Amphiboles)
Pink Granite
Phaneritic Quartz-Feldspar Granite