Chert (Arrowhead/Artifact Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Category
Browse organic crystal (mineraloid) specimens identified by the Rock Identifier community.
Chert (Arrowhead/Artifact Fragment)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Red Jasper
Jasper (Silicon Dioxide, SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Brown variety / Common Jasper)
Microcrystalline Quartz (SiO2)
Jasper (Green/Yellow Moss Jasper)
Silicon Dioxide (SiO2)
Anthracite Coal
Anthracite
Chert (Tan/Grey variety)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Wood Beads (Palmwood/Ebony)
Various species for wood, but often refers to woods like Palmwood (e.g., Borassus flabellifer) or Ebony (Diospyros spp.) for their distinctive grain and hardness.
Jasper (specifically Yellow Jasper and Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Red Jasper
Jasper (Silicon Dioxide with Iron inclusions - SiO2)
Banded Agate (specifically Moss Agate or Plume Agate variety)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (variations include Flint/Jasper)
Cryptocrystalline Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Opalite
Synthetic Opalised Glass
Moss Agate
Silicon Dioxide (SiO2) with inclusions
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Ferruginous Sandstone (Ironstone)
Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)
Petrified Wood
Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Graphite
Graphite (Native Carbon, C)
Chert (Nodule)
Silicon Dioxide (SiO2)
Shale (sub-type: Carbonaceous Shale)
Lutaceous Sedimentary Rock
Fossil Shell (Bivalve)
Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3
Yellow Jasper (Mookaite style)
Silicon Dioxide (SiO2) with Goethite/Hematite inclusions
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Cherty Flint/Jasper variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Pearl
Pearl (Calcium Carbonate with organic conchiolin, CaCO3)
Carved Mottled Greenish-Yellow Crystal/Glass Object
Unknown; possibly a form of quartz (chalcedony/jadeite/nephrite) or glass/resin.
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
Chert (specifically Iron-stained River Cobble)
Silicon Dioxide (SiO2)
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
Septarian Nodule (Dragon Stone)
Septarian Concretion (CaCO3 with Siderite and Calcite)
Jasper
Agate/Jasper (Microcrystalline Quartz, SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (Brecciated or Veined)
Silicon Dioxide (SiO2)
Green Calcite
Calcium Carbonate (CaCO3)
Green Banded Chert (Agate/Jasper)
Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite
Tufa
Calcareous Tufa (Calcium Carbonate, CaCO3)
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)