Quartz (Milky/Crystal Variety)
Silicon Dioxide (SiO2)
Category
Browse sedimentary rock (technically chert, a microcrystalline quartz) specimens identified by the Rock Identifier community.
Quartz (Milky/Crystal Variety)
Silicon Dioxide (SiO2)
Amethyst Lace Agate / Banded Amethyst
Silicon Dioxide (SiO2) with Fe3+ impurities
Clear Quartz crystals on a Matrix base (Geode fragment)
Silicon Dioxide (SiO2)
Chert / Greenstone
Silicon Dioxide (SiO2) with impurities
Sandstone (likely Arkosic)
Arenite (SiO2 with KAlSi3O8)
Quartzite River Rock
Quartzite (primarily SiO2)
Quartzite (River Cobble)
SiO2 (Quartz-rich Metamorphic Rock)
Milky Quartz Pebble with Chert
Silicon Dioxide (SiO2)
Common Opal in Host Rock
Hydrated Silica (SiO2·nH2O)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Hematite/Limonite) inclusions
Quartzite Pebbler
Quartzite (mainly SiO2)
Sandstone (likely Arkose)
Arenite (composed mainly of SiO2 with Feldspar)
Flint Nodule
Microcrystalline Quartz (SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with iron oxide cement)
Quartzite
Quartzite (primarily SiO2)
Chert (often called Flint)
Silicon Dioxide (SiO2)
Sandstone (specifically Banded Sandstone)
Clastic sedimentary rock (primarily SiO2)
Banded Iron Formation (BIF)
Magnetite-Hematite Chert (Banded Iron Formation)
Quartzite (Iron-stained)
Quartzite (SiO2 with Fe-oxides)
Druzy Quartz on Matrix (likely Limestone or Sandstone)
Silicon Dioxide (SiO2) with various trace impurities
Quartz (Milky/Vein Quartz)
Silicon Dioxide (SiO2)
Quartzite with Iron Inclusions
Quartzite (primarily SiO2)
Ruby
Corundum (Al2O3) with Chromium traces
Sandstone
Arenite (composed primarily of SiO2)
Geode (unopened) or Calcareous Nodule
Siliceous or Calcareous Concretion/Nodule
Quartz (Druzy)
Silicon Dioxide (SiO2)
Quartz Vein in River Siltstone
Crystalline Quartz (SiO2) in Siliclastic Matrix
Wishing Stone (Gneiss or Basalt with Quartz Vein)
Gneiss or Metabasalt (with a Quartz or Calcite intrusion)
Quartzite with Hematite staining
Quartzite (SiO2)
Fossil Coral (Rugose Coral Fragment)
Rugosa (extinct order of solitary and colonial corals)
Pebble or Cobble (likely composed of sandstone or conglomerate)
Clastic Sedimentary Rock (specific name like sandstone, conglomerate, or breccia would require microscopic analysis of clast size and angularity)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Rough Quartz (or Quartzite pebble)
Silicon Dioxide (SiO2)
River Pebble (Gravel)
Clastic sedimentary rock (likely Siltstone or Mudstone pebble; SiO2 with various impurities)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Oolitic Chert
Silicon Dioxide (SiO2) with Oolitic texture
Sandstone (Quartzite Pebble)
Arenite (SiO2)
Chert (specifically tan/pink variety)
Silicon Dioxide (SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2 with Cristobalite inclusions)
Quartzite
Quartzite (SiO2)
Chert (Jasper)
Silicon dioxide (SiO2)