Quartz (in a rock matrix)
Quartz (SiO2)
Category
Browse sedimentary (microcrystalline quartz) specimens identified by the Rock Identifier community.
Quartz (in a rock matrix)
Quartz (SiO2)
Jasper (Iron-stained Quartz)
Silicon Dioxide (SiO2) with iron oxide inclusions
Agate
Silicon dioxide (SiO2) - variety Chalcedony
Banded Agate
Silicon Dioxide (SiO2)
Dalmation Stone (Dalmation Jasper)
Peralkaline rock (primarily Feldspar and Quartz with Arfvedsonite spots)
Banded Chert or Chert with Quartz Veins
Chert (SiO2)
Fossilized Wood (Petrified Wood)
Silicified Wood (primarily quartz/chalcedony replacing organic matter)
Carnelian
Cryptocrystalline Quartz (SiO2 with iron oxide impurities)
Brecciated Jasper
Silicon Dioxide (SiO2) with Hematite and Quartz inclusions
Chalcedony (specifically Agate or Flint)
Silicon Dioxide (SiO₂)
Jasper (Iron-stained Quartz)
Silicon dioxide (SiO2) with iron oxide inclusions
Grey Jasper (Tumbled Quartz variant)
Jasper (Silicon Dioxide, SiO2)
River Pebble (Quartz-rich)
Silicon Dioxide (SiO2) with various inclusions
Quartzite and Chert
Silicon Dioxide (SiO2)
River Cobble (likely Basalt or Chert)
Siliceous River Rock / Microcrystalline Quartz / Mafic Igneous
Glauconitic Sandstone (Greensand)
Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
Carnelian
Carnelian (SiO2 - Silicon Dioxide with Iron Oxide impurities)
Agate
Silicon dioxide (SiO2)
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide inclusions
Zebra Rock (Zebra Stone / Ribbon Stone)
Siltstone with Ferruginous Banding (Primarily Quartz, Kaolinite, and Hematite)
Pink Botswana Agate
Silicon Dioxide (SiO₂), a cryptocrystalline variety of Quartz and Chalcedony
Weathered Quartzite or Chert Pebble
Silicon Dioxide (SiO2)
Jasper
Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)
Jasper (likely a variety of Yellow or Mustard Jasper)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Quartz Vein in Siltstone
SiO2 (Quartz) on clastic sedimentary matrix
Red Jasper
Quartz (Silicon Dioxide) with Iron Oxide impurities (Fe2O3)
River Pebble (likely Quartzite or Chert)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Fired Clay Brick (Anthropic Rock substitute)
Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)
Botryoidal Chalcedony (Druzy Quartz)
Silicon Dioxide (SiO2)
Quartzite (Milky)
Quartzite (SiO2)
Shiva Lingam
Cryptocrystalline Quartz (Jasproid/Sandstone) with Iron Oxide (Fe2O3)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Botryoidal Chalcedony (Agate/Carnelian)
Chalcedony (SiO2)
Orange Quartzite (Tumble-polished)
Quartzite (primarily SiO2)
Red Jasper with Quartz and Hematite
Silicon Dioxide (SiO2) with Ferric Iron inclusions
Quartzite
Quartzite (primarily SiO2)
Shale with Vein Infillings
Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.
Limonite-stained Chert/Jasper
Microcrystalline Quartz (SiO2) with Iron Oxides (FeO(OH)·nH2O)
Banded Agate
Cryptocrystalline Quartz (SiO2)
Jasper (Iron-rich)
Silicon Dioxide (SiO2) with Fe2O3 (Hematite) impurities
River Pebble (Quartz/Jasper)
Silicon Dioxide (SiO2)