Chert (specifically Jasper/Flint)
Chert (SiO2)
Category
Browse mineral, specifically a rock fragment specimens identified by the Rock Identifier community.
Chert (specifically Jasper/Flint)
Chert (SiO2)
Jasper (specifically Chert/Ironstone)
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Coquina
Coquina (Bioclastic Limestone)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Schist with Quartz Vein
Mica Schist with Crystalline Quartz (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Slate
Slate (foliated metamorphic rock)
Dark Igneous Rock (Likely Basalt or Diabase)
Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide impurities
Quartz Geode
Silicon Dioxide (SiO2)
Ferruginous Sandstone (Ironstone)
Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)
Quartz Vein on Matrix
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 based with mineral cement)
Milky Quartz
Silicon Dioxide (SiO2)
Mica Schist
Schist (Crystalline metamorphic rock)
Gneiss (Metamorphic Rock)
Gneiss
Quartzite
Quartzite (Primary mineral: SiO2)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Ocean Jasper
Orbicular Jasper (Silicon Dioxide with impurities), SiO2
Rose Quartz
Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Dyed Agate Geode (Pink/Magenta)
Silicon Dioxide (SiO2) - variety of Chalcedony/Quartz
Milky Quartz with Chlorite/Mica inclusions
Silicon Dioxide (SiO2) with inclusions
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Tree Agate
Dendritic Agate (Silicon Dioxide, SiO2)
Carnelian Agate (with Quartz/Chalcedony)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Basalt with Quartz/Plagioclase Inclusions
Mafic volcanic rock (Basaltic)
Basalt with Quartz Veins
Basalt (complex silicate) with Quartz (SiO2) intrusions
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Gneiss
Gneiss
Greenstone / Diorite
Intermediate plutonic igneous rock
Dalmatian Stone (Dalmatian Jasper)
Peralkaline Quartz-Feldspar Porphyry with Arfvedsonite
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Quartz (Milky or Smoky variety)
Silicon Dioxide (SiO2)
Mica Schist
Mica Schist
Granodiorite
Granodiorite (Intermediate intrusive igneous rock)
Rose Quartz
Silicon Dioxide (SiO2) with trace titanium, iron, or manganese
Basalt
Extrusive mafic igneous rock
Quartz pebble
Silicon dioxide (SiO2)
Vesicular Basalt
Basalt with secondary mineral infilling (Amygdaloidal Basalt)
Desert Varnish (on Sandstone)
Rock Varnish (composed of Manganese oxides, Iron oxides, and Clay minerals)
Ferruginous Sandstone (with possible Epidote/Chlorite coloring)
Sandstone (SiO2 dominated with Fe2O3 staining)