Sedimentary Rock (Technically Chert, A Microcrystalline Quartz)

Yellow Jasper

Chalcedony (Silicon Dioxide, SiO2)

Herkimer Diamond

Quartz (Silica - SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2

Chert (specifically White Chert or Novaculite)

Silicon Dioxide (SiO₂)

Puddingstone

Conglomerate (specifically a type of jasper conglomerate or quartz conglomerate)

Chert (Nodule)

Chert (Alpha-Quartz, SiO2)

Sandstone

Sandstone (clastic sedimentary rock)

Tree Agate

Silicon Dioxide (SiO2) - Dendritic Agate/Chalcedony

Marble

Recrystallized Calcite (CaCO3) Rock

Chert (often colloquially referred to as Flint)

Chert (Cryptocrystalline Quartz, SiO2)

Zebra Jasper

Silicon dioxide (SiO2) with various impurities

Agate Slices and Clear Quartz Points

Agate (SiO2 Chalcedony) and Clear Quartz (SiO2 Crystalline)

Quartz

Silicon dioxide (SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Yellow Quartzite River Cobble

Meta-quartzite (SiO2 with iron oxide staining)

Lapis Lazuli

Lapis Lazuli (A complex rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)

Mahogany Obsidian

Volcanic Glass (predominantly SiO2 with inclusions of Hematite or Magnetite)

Lapis Lazuli

Lapis Lazuli (Mineral composition: Lazurite (Na,Ca)8(AlSiO4)6(SO4,S,Cl,OH)2, Calcite, and Pyrite)

Chert (Green variety)

Chert (Silicon Dioxide, SiO2)

Quartz on Schist

Silicon Dioxide (SiO2) on Foliated Metamorphic Rock

Quartz Veined Basalt

Mafic Volcanic Rock with Microcrystalline Quartz (SiO2)

Chert / Flint

Chert (SiO2)

Chert (River Pebble)

Chert (SiO2)

Quartzite

Quartzite (SiO2)

Chert Conglomerate (or Breccia)

Sedimentary Clastic Rock (variety: Ferruginous Chert Breccia)

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Chert (River Stone/Pebble)

Chert (SiO2)

Quartz Vein in Host Rock (Likely Slate or Shale)

Hydrothermal Quartz (SiO2) in Pelitic host rock

Limonite-stained Chert/Jasper

Microcrystalline Quartz (SiO2) with Iron Oxides (FeO(OH)·nH2O)

Quartzite (Milky)

Quartzite (SiO2)

Quartzite

Quartzite (SiO2)

Carnelian (Chalcedony)

Cryptocrystalline Quartz (SiO2) with Iron Oxide impurities

Quartz (in a rock matrix)

Quartz (SiO2)

Chert (with Manganese Dendrites)

Chert (Cryptocrystalline Quartz, SiO2)

Yellow Chert (River Stone/Pebble)

Chert (Cryptocrystalline Quartz, SiO2)

River Pebble (Quartz-rich)

Silicon Dioxide (SiO2) with various inclusions

Chert (specifically Flint or Gray Chert)

Silicon Dioxide (SiO2)

Chert (Chert / Flint)

Silicon Dioxide (SiO2)

Glauconitic Sandstone (Greensand)

Glauconitic Quartz Arenite (containing Glauconite, (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)

Puddingstone (specifically Michigan/Gowganda Puddingstone)

Conglomerate (Jasper Conglomerate)

Chert (often called Flint)

Chert (SiO2)