Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Category
Browse sedimentary (microcrystalline silicate) specimens identified by the Rock Identifier community.
Banded Chert
Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)
Hag Stone (Banded Chert or Limestone with Borehole)
Microcrystalline Quartz (Chert) or Calciferous Siltstone (CaCO3/SiO2)
Laterite (iron-rich nodule, possibly Bauxite as a subtype)
Laterite (composed of various minerals including goethite, hematite, gibbsite, etc.)
Dalmatian Jasper (Dalmatian Stone)
Dalmatian Stone (primarily Feldspar, Quartz, and Arfvedsonite/Tourmaline)
Carnelian (Chalcedony variety)
SiO2 (Silicon Dioxide)
River Pebbles (Tumbled Quartz and Basalt)
Silicon Dioxide (SiO2) for white quartz; Mafic Volcanic Rock for basalt
River Pebble (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) mixture with varied clastic minerals
Quartz / Chert
Silicon Dioxide (SiO2)
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2
Banded Iron Formation (BIF) with Quartz
Banded Iron Formation, often composed of alternating layers of hematite (Fe2O3) or magnetite (Fe3O4) and chert (microcrystalline quartz, SiO2)
Red Jasper (beads)
SiO₂ (Silicon Dioxide)
River Pebble (likely Quartzite or Chert)
Silicon Dioxide (SiO2)
Jasper and Basalt Mix (Dark Chert/Basalt River Pebble)
Silicon Dioxide (SiO2) or Mafic extrusive igneous rock
River Pebble (likely Quartzite or Chert)
Silicon Dioxide (SiO2) crystal conglomerate
Jasper
Silicon Dioxide (SiO2) - a variety of Chalcedony (Cryptocrystalline Quartz)
Banded Iron Formation
Banded Iron Formation (BIF)
Petrified Wood
Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)
Limonite-stained Chert/Jasper
Microcrystalline Quartz (SiO2) with Iron Oxides (FeO(OH)·nH2O)
Limonite (after Pyrite Pseudomorph)
Limonite (Hydrated Iron Oxide Mixture, FeO(OH)·nH2O)
Jasper (Iron-rich Chalcedony)
Jasper (Microcrystalline Silicon Dioxide, SiO2 plus iron oxide impurities)
River Cobble (likely Basalt or Chert)
Siliceous River Rock / Microcrystalline Quartz / Mafic Igneous
Chert (Flint)
SiO2 (predominantly microcrystalline or cryptocrystalline quartz)
Jasper River Pebble
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Red Jasper
Red Jasper (variety of Chalcedony, SiO₂)
Chert or Flint (polished/water-worn)
Chert (a microcrystalline or cryptocrystalline variety of quartz, SiO2). Flint is a specific variety of chert.
River Rock (Quartz-dominated)
Silicon Dioxide (SiO2) mixture with varied clastic sediments
Jasper (likely a variety of Brecciated Jasper or a patterned variety)
Silicon dioxide (SiO2)
Fossil Coral
Coral Limestone (a type of biogenic sedimentary rock)
Wishing Stone (Basalt/Greywacke with Quartz Vein)
Basalt or Siltstone with SiO2 (Quartz) hydrothermal intrusion
Brown Jasper
Jasper (a cryptocrystalline variety of Quartz, SiO2)
Quartzite
Quartzite (primarily SiO2)
Red Jasper
Silicon Dioxide (SiO₂)
Fossiliferous Limestone
Limestone (composed primarily of calcite with included fossils CaCO3)
River Pebbles (Sandstone and Quartzite)
SiO2 (Quartz) dominated clastic rocks
Red Jasper
Jasper (Silicon Dioxide with Iron Oxide inclusions - SiO2)
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)
Red Swirl Beads (Likely Resin or Glass, simulating Red Jasper or Agate)
N/A (for the beads as pictured); Red Jasper: SiO2 (Chert variety); Red Agate: SiO2 (Chalcedony variety)
Agate (or Chalcedony)
SiO2 (Silicon Dioxide) - a cryptocrystalline variety of quartz
Agate (various color varieties)
SiO₂ (Silicon Dioxide)
Chert (variously known as Flint or Microcrystalline Quartz)
Silicon dioxide (SiO2)
Red Jasper (beads)
Silicon Dioxide (SiO2) with iron inclusions