Tumbled brown chalcedony (possibly carnelian or jasper)
Microcrystalline quartz, SiO₂; likely iron-stained chalcedony
Category
Browse sedimentary (cryptocrystalline quartz) specimens identified by the Rock Identifier community.
Tumbled brown chalcedony (possibly carnelian or jasper)
Microcrystalline quartz, SiO₂; likely iron-stained chalcedony
Green Jasper
Microcrystalline Quartz (SiO2)
Jasper
Microcrystalline Quartz (SiO2)
Chert (White/Gray variety)
Silicon Dioxide (SiO2 / Cryptocrystalline Quartz)
Chert / Flint Jasper
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chalcedony (Agate / Chert)
Silicon Dioxide (SiO2)
Chalcedony (Botryoidal or Chalcedony Rose)
Silicon dioxide (SiO2)
Quartz pebble
Silicon Dioxide (SiO2)
Jasper
Microcrystalline Quartz (SiO2)
Chert (Flint Nodules)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Flint with Chalk Cortex
Chert (Microcrystalline Quartz, SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert
Silicon dioxide (SiO2)
Chert
Chert (Microcrystalline Quartz, SiO2)
Chert (Common Opal/Chalcedony nodule)
Microcrystalline Quartz (SiO2)
Chalcedony (Jasper/Agate mix)
Quartz (microcrystalline SiO2)
Chert / Jasper
Silicon Dioxide (SiO2)
Chert (Yellow Jasper/River Pebble)
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)
Quartz (SiO₂)
Chert
Microcrystalline Quartz (SiO2)
Red Jasper (with Quartz)
Silicon Dioxide (SiO2) with Hematite inclusions
Carnelian (Chalcedony)
SiO2 (Silicon Dioxide with Iron Oxide inclusions)
Yellow Jasper Pebble
Silicon Dioxide (SiO2) with Iron Oxide inclusions
Chert (Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chalcedony
Chalcedony (SiO2)
Geode with Quartz and possibly Jasper/Hematite
Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides
Petrified Wood
Silicified Wood (SiO2)
Chert
Silicon Dioxide (SiO2)
Chert (variant of Flint)
Chert (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Brown Chert
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chalcedony (specifically Agate or Carnelian variety)
Cryptocrystalline Silica (SiO2)
Polished red jasper (likely hematite-bearing jasper)
Jasper, microcrystalline quartz (SiO₂), colored chiefly by iron oxides such as hematite/goethite
Carnelian
Chalcedony (cryptocrystalline quartz), SiO2 (Silicon Dioxide)
Chert (Arrowhead)
Microcrystalline Quartz (SiO2)