Igneous Rock (Volcanic Glass)

Vesicular Basalt (or Porphyritic Scoria)

Vesicular Basalt

Agate (specifically Waterline or Onyx-type Agate)

Silicon Dioxide (SiO2) - variety Chalcedony

Basalt with Phenocrysts (Porphyritic Basalt)

Porphyritic Basalt (primarily Plagioclase and Pyroxene)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with Goethite/Iron oxide inclusions

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Milky and Citrine-type Quartz

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Obsidian (Apache Tear)

Obsidian / Amorphous Volcanic Glass (main component: SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Magnetite (potentially as a Lodestone or within Ironstone)

Magnetite (Fe3O4)

Quartz (Milk Quartz / Massive Quartz)

Silicon Dioxide (SiO2)

Chert (Common Opal/Chalcedony mixture)

Silicon Dioxide (SiO2)

Quartz / Calcite Vein Rock

Silicon Dioxide (SiO2) or Calcium Carbonate (CaCO3)

Granite

Phaneritic Plutonic Felsic Rock

Granite

Granite (Felsic Plutonic Rock)

Quartz with Mica inclusions (likely Schist or Gneiss host)

Silicon Dioxide (SiO2) with Phyllosilicates (KAl2(AlSi3O10)(OH)2)

Quartz (Citrine or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Diabase (Greenstone Pebble)

Diabase or Dolerite

Smoky Quartz Geode Slice

Silicon Dioxide (SiO2)

Basalt

Vesicular Basalt

Orthoclase Feldspar (or K-Feldspar)

Orthoclase (KAlSi3O8)

Quartz (Milky/Crystal Variety)

Silicon Dioxide (SiO2)

Porphyritic Basalt

Porphyritic Basalt (with plagioclase phenocrysts)

Clear Quartz Cluster

Quartz (Silicon Dioxide - SiO2)

Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Red Granite

Felsic intrusive igneous rock (K-feldspar rich Granite)

Smoky Quartz

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Granite Pebble (Salt and Pepper Granite)

Felsic Intrusive Igneous Rock (Granite)

Red Jasper

Jasper (Silicon Dioxide, SiO2 with Iron Oxide impurities)

Basalt with Weathered Surface

Basalt

Clear Quartz

Silicon Dioxide (SiO2)

Black Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Obsidian

Obsidian (Volcanic glass), 70-75% SiO2

Diorite (Salt and Pepper Rock)

Diorite

Diorite (Salt and Pepper Rock)

Diorite

Quartz (Water-worn pebble)

Silicon Dioxide (SiO2)

Jasper with Quartz inclusion

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Granodiorite / Granite

Granodiorite (containing Quartz SiO2, Plagioclase Feldspar, and Biotite)

Basalt with Mineral Vein (Cobble)

Basalt (with likely Quartz/Calcite vein)

Chalcedony (Common Agate)

Silicon Dioxide (SiO2)