Organic Gemstone (Not A Mineral)

Mother of Pearl and Onyx

Aragonite (Mother of Pearl) and Chalcedony (Onyx)

Chert (Jasper variety)

Microcrystalline Quartz (SiO2)

Fossilized Fish Skeleton in Matrix

Vertebrata (Class: Actinopterygii), typically found in limestone or shale matrices

Petrified Dinosaur Bone (Gembone)

Agatized Dinosaur Bone

Jasper

Silicon dioxide (SiO2)

Jasper Agate

Silicon dioxide (SiO2)

Chalcedony (Common Opal variant)

Silicon dioxide (SiO2) with varying levels of hydration

Chert (Brown Variety)

Silicon dioxide (SiO2)

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Geode (unopened)

Chert / Chalcedony Geode (SiO2)

Banded Chert

Silicon dioxide (SiO2)

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 principal component)

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Jasper with Agate and Quartz Inclusions

Silicon Dioxide (SiO2) - Chalcedony / Quartz aggregate

Chert (Pink variety)

Microcrystalline Quartz (SiO2)

Amber

Succinite

Petrified Wood

Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)

Chert (Flint Nodules)

Chert (Microcrystalline Quartz, SiO2)

Chert / Flint

Chert (varieties include Flint)

Amazonite

Potassium Feldspar (KAlSi3O8)

Chert (specifically Red Chert/Jasper variety)

Silicon Dioxide (SiO2)

Glauconitic Sandstone

Glauconitic Quartz Arenite

Shale with Coprolite influence

Argillaceous sedimentary rock (Shale/Mudstone)

Megalodon Shark Tooth (Partial Fossil)

Otodus megalodon (fossilized in Calcium Phosphate/Apatite)

Fossilized Shark Tooth

Fossilized elasmobranch tooth (Apatite/Calcium Phosphate)

Glauconitic Sandstone

Glauconitic Quartz Arenite

Petrified Wood

Silicified Wood (SiO2)

Chert (Flint with Iron Staining)

Silicon Dioxide (SiO2)

Green Quartz (Prasiolite)

Crystalline Silicon Dioxide (SiO2)

Ammolite

Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)

Chert (specifically Tan/Yellow Chert)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood

Silicified Wood (SiO2)

Amber

Fossilized tree resin

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Chert (Brecciated Chert)

Silicon Dioxide (SiO2)

Emerald in Matrix

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Amazonite

Microcline (K(AlSi3O8))

Citrine Quartz

Silicon Dioxide (SiO2) with ferric iron impurities

Emerald in Matrix

Emerald (Beryllium Aluminum Silicate - Be3Al2(SiO3)6)

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Botryoidal Chalcedony

Silicon Dioxide (SiO2)