Amethyst
Amethyst (Silicon Dioxide, SiO2)
mineral
Dyed Agate
Silicon Dioxide (SiO2) - variety Chalcedony
mineral
Carnelian Agate
Silicon Dioxide (SiO2) with iron oxide impurities
mineral
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)3Si3O10(OH)2)
metamorphic
Corundum (Ruby Variety)
Corundum (Al2O3)
mineral
Satin Spar (Selenite)
Gypsum (CaSO4·2H2O)
mineral
Orange Quartzite / Carnelian Agate
Silicon Dioxide (SiO2)
metamorphic
Blue Moss Agate / Blue Chalcedony
Silicon Dioxide (SiO2)
mineral
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
metamorphic
Amethyst (Tumbled)
Amethyst (Silicon Dioxide, SiO2 + Fe4+)
mineral
Chevron Amethyst
Silicon Dioxide (SiO2) with trace Iron (Fe4+)
mineral
Fluorite
Calcium Fluoride (CaF2)
mineral
Smoky Quartz
Silicon Dioxide (SiO2)
mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Greenschist (Greenstone)
Greenschist
metamorphic
Serpentine (Serpentinite)
Serpentinite (complex silicate group including lizardite, chrysotile, and antigorite)
metamorphic
Chert (Jasper/Mudstone)
Silicon Dioxide (SiO2)
sedimentary
Travertine
Calcareous tufa (CaCO3)
sedimentary
Banded Agate (Carnelian type)
Silicon Dioxide (SiO2) - Cryptocrystalline Chalcedony
mineral
Black Obsidian
Obsidian (Amorphous volcanic glass, SiO2)
igneous
Amazonite
K(AlSi3O8) - Microcline
mineral
Citrine (Heat-treated Amethyst)
Silicon Dioxide (SiO2) with iron impurities
mineral
Blue Kyanite
Kyanite (Al2SiO5)
mineral
Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
mineral
Gneiss
Gneiss (High-grade metamorphic rock)
metamorphic
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Mineral
Turquoise in Matrix
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Kaolinite (Chalky Clay)
Kaolinite (Al2Si2O5(OH)4)
sedimentary
Chert (specifically Flint or Jasper variant)
Microcrystalline quartz (SiO2)
sedimentary
Specular Hematite
Specularite (Iron Oxide, Fe2O3)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
mineral
Basalt
Basalt (composition predominately Plagioclase feldspar and Pyroxene)
igneous
Quartzite River Rock
Metamorphic Quartzite (primarily SiO2)
metamorphic
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Dendritic Agate
Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)
mineral
Dyed Pumice
Vesicular Rhyolite (Artificial Coloration Addition)
igneous
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
River Rock (Quartzite/Chert conglomerate)
Quartzite (SiO2)
metamorphic
Quartzite
Quartzite (primarily SiO2)
metamorphic
Quartzite River Rock
Quartzite (primarily SiO2)
metamorphic