Amethyst
Amethyst (Silicon Dioxide, SiO2)
mineral
Red Jasper
Silicon Dioxide with Iron Oxide (SiO2)
sedimentary
Unakite
Epidotized Granite
metamorphic
Travertine
Terrestrial Sedimentary Limestone (CaCO3)
sedimentary
Lapis Lazuli
Lapis Lazuli (Complex silicate: Na8[Al6Si6O24]Sn)
metamorphic
Snowflake Obsidian
Spherulitic Obsidian (primarily SiO2)
igneous
Rose Quartz
SiO2 (Silicon Dioxide with trace inclusions of dumortierite)
mineral
Dalmatian Jasper
Peralkaline rhyolite with Arfvedsonite inclusions
igneous
Basalt (River Pebble)
Extrusive mafic igneous rock
igneous
Liesegang Banded Sandstone (Wonderstone)
Ferruginous Sandstone with Liesegang Rings
sedimentary
Granodiorite with Biotite Mica
Granodiorite (containing Quartz, Plagioclase Feldspar, and Biotite Mica)
igneous
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and clay impurities
sedimentary
Blue Calcite
Calcium Carbonate (CaCO3)
mineral
Blue Calcite
Calcium Carbonate (CaCO3)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz (Milky/Crystalline variety)
Silicon Dioxide (SiO2)
mineral
Obsidian
Obsidian (Volcanic Glass)
igneous
Limestone
CaCO3 (principally composed of Calcite)
sedimentary
Chert Nodule (with Flint core)
Sedimentary Cryptocrystalline Quartz (SiO2)
sedimentary
Jasper Chert Nodules
Silicon Dioxide (SiO2) with Hematite impurities
sedimentary
Nephrite Jade
Ca2(Mg,Fe)5Si8O22(OH)2
metamorphic
Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz Vein with Iron Staining
Silicon Dioxide (SiO2)
mineral
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Granite
Phaneritic Felsic Intrusive Igneous Rock
igneous
Quartzite
Quartzite (SiO2)
metamorphic
Jasper
Jasper (Cryptocrystalline variety of Quartz, SiO2)
sedimentary
Greenstone / Diorite
Intermediate plutonic igneous rock
igneous
Basalt
Extrusive mafic igneous rock
igneous
Sandstone with Liesegang Rings
Arenite with Iron Oxide Liesegang Banding
sedimentary
River Stone (Quartzite/Siltstone mixture)
Silicon Dioxide (SiO2) based metamorphosed sandstone
metamorphic or sedimentary
Basalt
Extrusive mafic igneous rock
igneous
Sandstone
Arenite (SiO2 based)
sedimentary
Amethyst (Rough Quartz)
Silicon Dioxide (SiO2) with iron impurities
mineral
Quartzite
Quartzite (SiO2)
metamorphic
Granite Glacial Erratic
Granite (Phaneritic Quartz-Feldspar Plutonic Rock)
igneous
Sulfur (on Matrix)
Native Sulfur (S8)
mineral
Quartz Druzy on Matrix (with Copper Mineralization)
Silicon Dioxide (SiO2) with Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·n H2O)
mineral
Granite
Granite (Felsic Plutonic Rock)
igneous
Shale
Fissile Mudstone
sedimentary
Granodiorite
Phaneritic Granodiorite
igneous
Amazonite
Potassium Feldspar (Microcline), K(AlSi3O8)
mineral