Organic Gemstone (Sedimentary Associations)

Ambergris

Ambergris (Coprolite-adjacent organic substance)

Purple Agate (Dyed Chalcedony)

SiO2 (Silicon Dioxide) with organic dyes

Quartz (Small Fragment)

Silicon Dioxide (SiO2)

Carnelian Agate

Silicon Dioxide with Hematite impurities (SiO2 + Fe2O3)

Quartz (likely) or a Quartzite Pebble

Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.

Pearl

Calcium Carbonate (Aragonite) - CaCO3

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Chalcedony Geode

Chalcedony (SiO2) within a geode structure

Milky Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Amber

Succinite (fossilized resin); C10H16O

Chert (Jasper/Carnelian variety)

Microcrystalline Quartz (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Red Jasper

Silicon Dioxide (SiO₂)

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz

SiO2 (Silicon Dioxide)

Garnet (Almandine/Pyrope variety)

Silicate mineral group; typically Fe3Al2(SiO4)3 (Almandine) or Mg3Al2(SiO4)3 (Pyrope)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Garnet Schist

Almandine Garnet-bearing Mica Schist

Aragonite (Star Cluster or Twinned variety)

Aragonite (Calcium Carbonate, CaCO3)

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Amber

Succinite

Amber

Succinite (specifically for Baltic amber); Complex mixture of organic compounds (C10H16O)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides

Amber

Succinite (C10H16O)

Fluorite

Calcium Fluoride (CaF2)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide

Tahitian Pearl

Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3

Shungite

Shungite (Non-crystalline carbon, C)

Shungite (Noble/Type II)

Non-crystalline carbon (Fullerene-bearing carbonaceous rock)

Turquoise with Pyrite

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O] with Iron Pyrite (FeS2)

Chalcedony (Agate/Carnelian)

Cryptocrystalline Quartz (SiO2)

Carnelian

Cryptocrystalline Quartz (SiO2 with iron oxide impurities)

Chert (specifically Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Aventurine (likely Green Aventurine)

Quartz (SiO2) with included minerals (Fuchsite or Chlorite for green color)

Ambergris

Ambergris (Coprolite-adjacent/Organic secretion)

Kyanite

Kyanite (Al2SiO5)

Peridot

Olivine (Mg, Fe)2SiO4

Amber

Succinite (a specific common type) or Fossilized Tree Resin (C10H16O)

Carnelian

Carnelian (a variety of Chalcedony, which is a microcrystalline quartz, SiO2)

Shungite

Non-crystalline carbon (Fullerenes / Carbon-60)