Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Category
Browse organic crystal (mineraloid) specimens identified by the Rock Identifier community.
Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Crinoid Stem Fossil (Indian Bead)
Crinoid ossicle (Echinodermata)
Chert (Flint Nodule)
Microcrystalline and Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (variant Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert / River Pebble
Microcrystalline Silica (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert / Flint
Chert (Cryptocrystalline Quartz, SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with iron oxide and other mineral impurities
Dragon Stone
Ohko Stone (Argillaceous sedimentary rock)
Petrified Wood
Silicified Wood (SiO2)
Sandstone
Arenicola (comprising mostly Quartz, SiO2)
Petrified Wood
Silicified Wood (primarily SiO₂)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (specifically Jasper/Flint pebble)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert with Quartz Druzy
Microcrystalline Quartz (SiO2) with Drusy Quartz Coating
Chert (Flint variety)
Chert (Microcrystalline or Cryptocrystalline Quartz), SiO2
Calcareous Tufa
Tufa (Calcium Carbonate, CaCO3)
Chert (specifically Jasper or Flint type)
Microcrystalline Quartz (SiO2)
Shale (possibly Carbonaceous or Oil Shale)
Argillaceous Sedimentary Rock
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement) SiO2
Petrified Wood
Silicified Wood (SiO2)
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Petrified Wood
Silicified Wood (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Chert (Green variety)
Chert (Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Jasper/Flint variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Silica (SiO2)
Banded Chert
Microcrystalline silicon dioxide (SiO2)
Chert (Jasper/Common Opal transition)
Microcrystalline Quartz (SiO2) with iron oxide inclusions
Petrified Wood
Silicified Wood (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Chert (specifically Chalcedony or Flint variation)
Microcrystalline Quartz (SiO2)
Chert (Gravel specimen)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Peacock Ore
Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with iridescent tarnish
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides
Honey Calcite
Calcium Carbonate (CaCO3)