Mineral, Specifically A Detrital Grain

Quartzite

Quartzite (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Basalt with Quartz/Calcite Veins

Basalt (Aphanitic Mafic Volcanic Rock) with Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3) inclusions

Ferruginous Sandstone (Ironstone)

Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)

Greenschist

Greenschist facies rock

Quartz in Host Rock

Silicon Dioxide (SiO2) in Rhyolite or Granite matrix

Quartzite

Quartzite (SiO2)

Quartzite (Nodule)

Quartzite (SiO2)

Quartzite

Quartzite (primarily SiO2)

Quartzite

Quartzite (composed primarily of SiO2)

Quartzite River Rock

Quartzite (SiO2)

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock)

Biotite Schist

Biotite Schist (predominantly K(Mg,Fe)3AlSi3O10(OH,F)2)

Jasper

Jasper (Silicon Dioxide, SiO2)

Quartz-veined Basalt

Amygdaloidal or Porphyritic Basalt with Silicon Dioxide (SiO2) vein

Granite

Phaneritic Igneous Rock (Granite)

River Siltstone Pebble

Siltstone (primarily composed of silica and clay minerals)

Glauconitic Sandstone

Glauconitic Sandstone (contains (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)

Basalt River Stone

Basalt

Granite

Granite (Alkali-feldspar, Quartz, and Plagioclase composition)

Shale (Beach-worn)

Laminated Pelite (primarily clay minerals and quartz)

Shale (sub-type: Carbonaceous Shale)

Lutaceous Sedimentary Rock

Granite

Granite (High-silica plutonic rock)

Basaltic Tuff / Volcanic Breccia

Pyroclastic Breccia / Lithic Tuff

Granite

Granite (Phaneritic Quartz-Feldspar Igneous Rock)

Gneiss (High-grade Metamorphic Rock)

Gneiss (Metamorphic silicate rock)

Greenstone / Diorite

Intermediate plutonic igneous rock

Basalt with Desert Varnish

Mafic Volcanic Rock (Fe/Mg rich Silicate)

Basalt (Crushed Roadstone)

Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)

Olivine (Peridot)

Magnesium Iron Silicate (Mg, Fe)2SiO4

Diorite

Diorite (Intermediate intrusive igneous rock)

Granitic Gneiss

Gneiss (High-grade Metamorphic Rock)

Chert (specifically Red Chert or Jasper)

Microcrystalline Quartz (SiO2)

Chert (specifically Jasper/Brown Chert)

Silicon Dioxide (SiO2)

Chert (specifically Red Chert or Jasper)

Microcrystalline Quartz (SiO2)

Chert (specifically Flint or Dark Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Red Chert / Flint)

Silicon Dioxide (SiO2)

Chert (specifically Green Chert/Jasper)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Chert (specifically Tan/Gray Chert)

Microcrystalline quartz (SiO2)

Chert (specifically Gray/Banded Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (specifically Tan/Yellow Chert)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)