Rock Identifier

Category

Organic Gemstone (Mineraloid)

Browse organic gemstone (mineraloid) specimens identified by the Rock Identifier community.

Learn about Organic Gemstone (Mineraloid) in the encyclopedia

Jet

Chert (Flint) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Cryptocrystalline Quartz (SiO2)

Baroque cultured pearl necklace (Pearl: nacre composed mainly of aragonite (CaCO₃) and conchiolin) — gemstone

Baroque cultured pearl necklace

Pearl: nacre composed mainly of aragonite (CaCO₃) and conchiolin

Pearl (Pearl; primarily aragonite (CaCO₃) with conchiolin) — gemstone

Pearl

Pearl; primarily aragonite (CaCO₃) with conchiolin

Polished moss agate (likely dendritic agate) (Chalcedony, microcrystalline quartz (SiO₂), with inclusions of manganese/iron oxides or hornblende) — gemstone

Polished moss agate (likely dendritic agate)

Chalcedony, microcrystalline quartz (SiO₂), with inclusions of manganese/iron oxides or hornblende

Tumbled amber (Fossilized plant resin; commonly succinite (C10H16O)) — gemstone

Tumbled amber

Fossilized plant resin; commonly succinite (C10H16O)

Moss Agate (Silicon Dioxide (Chalcedony with green mineral inclusions), SiO2) — gemstone

Moss Agate

Silicon Dioxide (Chalcedony with green mineral inclusions), SiO2

Amber (Raw Copal) (Fossilized Plant Resin (Gummite/Succinite)) — mineral

Amber (Raw Copal)

Fossilized Plant Resin (Gummite/Succinite)

Moss Agate (Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions) — mineral

Moss Agate

Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions

Mookaite Jasper (Silicon Dioxide with Iron Oxide impurities (SiO2)) — mineral

Mookaite Jasper

Silicon Dioxide with Iron Oxide impurities (SiO2)

Petrified Wood (Silicified wood (Quartz/Chalcedony - SiO2)) — mineral

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Jasper (Jasper (Cryptocrystalline variety of Quartz, SiO2)) — sedimentary

Jasper

Jasper (Cryptocrystalline variety of Quartz, SiO2)

Yellow-brown translucent mineral fragment, likely citrine or amber (Quartz (SiO₂), if citrine; succinite (fossil resin), if amber) — mineral

Yellow-brown translucent mineral fragment, likely citrine or amber

Quartz (SiO₂), if citrine; succinite (fossil resin), if amber

Amber (Succinite (fossilized resin)) — mineral

Amber

Succinite (fossilized resin)

Chert (specifically Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Pearl (Organic Mineral (CaCO3 with conchiolin)) — mineral

Pearl

Organic Mineral (CaCO3 with conchiolin)

Red Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Petrified Wood (Silicified Wood (SiO2)) — fossil

Petrified Wood

Silicified Wood (SiO2)

Chert (Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides) — mineral

Moss Agate

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

Opalite (Synthetic Opalite Glass (Silicon Dioxide)) — mineraloid (man-made)

Opalite

Synthetic Opalite Glass (Silicon Dioxide)

mineraloid (man-made)

Jasper (Jasper (Silicon Dioxide) - SiO2) — sedimentary

Jasper

Jasper (Silicon Dioxide) - SiO2

Chert (Jasper/Agate variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Chert (Jasper/Flint variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Red Chert (Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Red Chert (Jasper)

Silicon Dioxide (SiO2)

Chert (Yellow Jasper/Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Jasper/Flint)

Silicon Dioxide (SiO2)

Fossil bivalve shell (Ribbed pectinid or related bivalve; originally calcite/aragonite (CaCO₃), likely partially mineralized) — fossil

Fossil bivalve shell

Ribbed pectinid or related bivalve; originally calcite/aragonite (CaCO₃), likely partially mineralized

Chert (specifically Flint or Common Chert) (Silicon dioxide (SiO2) - Microcrystalline quartz) — sedimentary

Chert (specifically Flint or Common Chert)

Silicon dioxide (SiO2) - Microcrystalline quartz

Chert (variations include Flint or Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (variations include Flint or Jasper)

Silicon Dioxide (SiO2)

Chert (Green variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Green variety)

Silicon Dioxide (SiO2)

Natural Pearl (appearing in a jewelry setting) (Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin) — mineral

Natural Pearl (appearing in a jewelry setting)

Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin

Fossil Coral (Phylum Cnidaria / Rugosa or Tabulata) — fossil

Fossil Coral

Phylum Cnidaria / Rugosa or Tabulata

Jasper (Petrified Wood variant) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper (Petrified Wood variant)

Silicon Dioxide (SiO2) with iron oxide inclusions

Amber (Fossilized Tree Resin (C10H16O)) — gemstone

Amber

Fossilized Tree Resin (C10H16O)

Chert (Jasper/Chalcedony pebble) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Chalcedony pebble)

Microcrystalline Quartz (SiO2)

Chert (Jasper) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper)

Cryptocrystalline Quartz (SiO2)

Chert Nodule (Fossiliferous Chert) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Nodule (Fossiliferous Chert)

Microcrystalline Quartz (SiO2)

Chert (often called Flint or Agate nodule) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Agate nodule)

Cryptocrystalline Quartz (SiO2)

Chert (var. Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (var. Jasper)

Microcrystalline Quartz (SiO2)

Chert (Blue-Gray Chert) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Blue-Gray Chert)

Microcrystalline quartz (SiO2)

Turquoise-and-coral silver jewelry brooch (Turquoise: hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O; red cabochons appear to be coral, likely set in silver) — gemstone

Turquoise-and-coral silver jewelry brooch

Turquoise: hydrated copper aluminum phosphate, CuAl₆(PO₄)₄(OH)₈·4H₂O; red cabochons appear to be coral, likely set in silver

Amber (likely Baltic amber) (Fossilized tree resin; chiefly polymerized diterpenoid resin (succinite)) — gemstone

Amber (likely Baltic amber)

Fossilized tree resin; chiefly polymerized diterpenoid resin (succinite)