Flint or chert flake
Microcrystalline quartz (SiO₂), commonly chalcedony with possible impurities
Category
Browse mineral or sedimentary (if chert) specimens identified by the Rock Identifier community.
Flint or chert flake
Microcrystalline quartz (SiO₂), commonly chalcedony with possible impurities
Chert (with Chalky Cortex)
Silicon Dioxide (SiO2)
Oolitic Chert
Silicon Dioxide (SiO2) with Oolitic texture
Red jasper (iron-rich chert), possibly brecciated
Jasper: microcrystalline quartz (SiO₂) colored mainly by hematite/goethite; likely chert/jasper with iron-oxide veining
Geode (unopened)
SiO2 - Chert-shelled concretion (mostly Quartz)
Chert with Quartz Veins
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Likely chert or jasper fragment
Microcrystalline quartz (SiO₂), probably iron-stained chert/jasper
Chert with Limestone matrix
Microcrystalline silica (SiO2) in Calcite (CaCO3) matrix
Chert Breccia
Brecciated Chert (Microcrystalline Silica)
Chert (Flint with Iron Staining)
Silicon Dioxide (SiO2)
Chert (specifically Red Chert/Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Silica (SiO2)
Chert (Iron-stained)
Silicon Dioxide (SiO2) with Iron Oxides
Banded Chert
Silicon Dioxide (SiO2)
Chert/Flint nodule or weathered river rock
Microcrystalline or cryptocrystalline silica (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Wood Jasper
Siliceous sedimentary rock (variety of Chert/Chalcedony)
Agate (Chert/Chalcedony)
Silicon Dioxide (SiO2)
Quartz-rich rock fragment, possibly chert or weathered quartz
Microcrystalline quartz (SiO₂), tentative identification
Chert (Iron-stained)
Microcrystalline quartz (SiO2)
Polished brown river pebble (likely chert or fine-grained sandstone)
Indeterminate; probable microcrystalline quartz (chert) or quartz-rich sandstone
Chert Concretion (Flint)
Silicon Dioxide (SiO2)
Sandstone Chert Concretion
Silica-cemented Concretion (primarily SiO2)
Dendritic Chert
Silicon Dioxide with Manganese Oxide Inclusions (SiO2 + MnO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Conglomerate Pebble (with Chert / Quartz)
Sedimentary Conglomerate / Breccia Pebble
Chert (Quartz-rich)
Microcrystalline Silica (SiO2)
Chert (Limestone-based)
Silicon dioxide (SiO2)
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
Chert (specifically Jasper/Carnelian variety)
Microcrystalline quartz (SiO2)
Chert (Jasper/Mudstone)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Yellow Chert (Jasper)
Silicon Dioxide (SiO2)
Chert / River Jasper
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Likely chert (flint)
Microcrystalline quartz (SiO₂), commonly called chert; identification from the photo is tentative.
Chert / Flint Nodule
Microcrystalline quartz (SiO2)
Chert or chalcedony fragment
Microcrystalline quartz (SiO₂), likely ferruginous or jasper-like chalcedony
Banded Chert
Microcrystalline Quartz (SiO2)
Weathered chert or siliceous limestone
Microcrystalline quartz (SiO₂), possibly with carbonate matrix
Yellow-brown quartz-rich pebble (possibly iron-stained chert or quartzite)
Quartz (SiO₂), likely with iron-oxide staining; exact identification requires hardness and acid tests