Sedimentary Rock (Technically A Microcrystalline Quartz Mineral Aggregate)

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Quartz (Milk Quartz / Massive Quartz)

Silicon Dioxide (SiO2)

Clear Quartz Crystal

Quartz (Silicon Dioxide, SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Flint Pebbles)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz

Silicon Dioxide (SiO2)

Chert (Field Stone)

Chert (SiO2)

Lake Superior Agate

Cryptocrystalline Quartz (SiO2)

Chert (often called Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartzite with Iron Inclusions

Metamorphic Quartzite (SiO2 with Fe2O3 trace impurities)

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2 + Manganese/Iron oxides)

Quartz (Milky/Granular)

Silicon Dioxide (SiO2)

Druzy Quartz Geode (Oco or Moroccan variety)

Silicon Dioxide (SiO2)

Agate

Silicon Dioxide (SiO2) - Chalcedony variant

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (River Cobble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (specifically Gray/Banded Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Gravel / Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (variously known as Flint or River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Tiger's Eye (Rough)

Pseudomorph of Quartz after Crocidolite (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

Chert / Flint Nodules

Cryptocrystalline Quartz (SiO2)

Limestone with Chert or Siltstone bands

Sedimentary carbonate rock (CaCO3) often with siliceous impurities

Sandstone

Arenite (composed primarily of SiO2)

Carnelian

Carnelian (SiO2)

Chert (specifically Gray/Black Chert)

Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Breciated Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sandstone or Siltstone

Arenite (if sandstone)

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Yellow variety / Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Lapis Lazuli (Lazurite crystals on Marble)

Lazurite / (Na,Ca)8[(S,Cl,SO4,OH)2|(AlSiO4)6]

Quartz Geode (with possible Manganese or Goethite coating)

Silicon Dioxide (SiO2)

Quartz / Quartzite

Silicon Dioxide (SiO2)

Basalt with Calcite Veins

Basalt (containing CaCO3 inclusions)

Dalmatian Stone

Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)

Chert (Nodule)

Silicon Dioxide (SiO2)

Chert (Nodule)

Silicon dioxide (SiO2) - Cryptocrystalline Quartz

Chert / Flint Conglomerate

Silicified Sedimentary Breccia (primarily SiO2)