Aragonite
Aragonite (CaCO3)
mineral
Category
Mineral Like Biological Tissue
Browse mineral like biological tissue specimens identified by the Rock Identifier community.
Fossiliferous Limestone (Coral Fossil)
Scleractinian Coral in Calcium Carbonate (CaCO3)
sedimentary
Bivalve Fossil (Clam/Mollusk)
Class: Bivalvia (Order: Veneroida), Calcium Carbonate (CaCO3)
sedimentary
Petoskey Stone
Hexagonaria percarinata (Fossilized Coral)
sedimentary
Goldfish Cracker (Culinary Mimic)
Cibus aurum (Commonly composed of Enriched Wheat Flour and Cheddar Cheese)
Anthropogenic Sedimentary-style Organic Solid
Amber
Succinite (specifically for Baltic amber); Complex mixture of organic compounds (C10H16O)
Organic Mineraloid
Amber
Succinite (a variety of fossilized tree resin); chemical formula appx. C10H16O
mineraloid
Amber
Succinite (C10H16O)
Organic Mineraloid
Amber
Succinite
Organic (Mineraloid)
Desert Varnish (on Sandstone)
Rock Varnish (composed of Manganese oxides, Iron oxides, and Clay minerals)
sedimentary
Amber
Fossilized tree resin (not a true mineral as it is organic and amorphous); Chemical formula is highly variable, but often approximated as C10H16O.
Mineral
Shell Cameo
Cypraecassis rufa (Bullmouth Queen Helmet Shell)
mineraloid / biogenic specimen
Hag Stone (Banded Chert or Limestone with Borehole)
Microcrystalline Quartz (Chert) or Calciferous Siltstone (CaCO3/SiO2)
sedimentary
Shungite
Carbonaceous rock (primarily amorphous carbon)
Mineraloid
Calcite
Calcite (CaCO3)
Mineral
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Honeycomb Coral Fossil
Favosites (extinct genus of tabulate coral)
sedimentary
Banded Iron Formation (BIF)
Banded Iron Formation
Sedimentary Rock
Amber
Succinite (specific to Baltic amber), fossilized tree resin
mineraloid
Coquina / Fossiliferous Limestone
Coquina (composed primarily of Calcium Carbonate / CaCO3)
sedimentary
Orange Calcite
Calcite (CaCO3)
Mineral
Jasper (Milky/Cream Variety)
Silicon Dioxide (SiO2) - variety of Chalcedony
sedimentary (chemical/biological)
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Crinoid Stem Fossil
Class Crinoidea (Phylum Echinodermata), primarily Calcium Carbonate (CaCO3)
sedimentary
Fossiliferous Limestone (Crinoidal)
Bioclastic Limestone (predominantly CaCO3)
sedimentary
Amber
Succinite (Approximate formula: C10H16O)
Mineraloid
Amber
Succinite (fossilized tree resin)
mineraloid
Pearls
Aragonite (calcium carbonate) and Conchiolin
Mineraloid
Mother of Pearl (Nacre)
Calcium Carbonate (primarily aragonite, with conchiolin)
Organic Gemstone/Biomineral
Sulfur on Aragonite
Sulfur (S) and Aragonite (CaCO3)
Mineral
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Potassium-Rich Silicate Clay (inferred from biological context)
Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)
mineral
Fossiliferous Limestone (Crinoidal)
Crinoid Limestone (CaCO3 with fossil biological remains)
sedimentary
Pearl
Calcium Carbonate (Aragonite or Calcite) and Conchiolin
Mineraloid
Amber
Succinite (specifically for Baltic amber; general formula C10H16O)
Mineraloid (Organic)
Limestone (Weathered)
Calcium Carbonate (CaCO3)
sedimentary
Note: Image shows a biological specimen (Rat), not a rock. Representative geological equivalent: Galena (due to lead-grey colors in fur).
Galena (PbS)
mineral
Ambergris
Ambrein (C30H52O)
mineraloid / organic geological substance
Limestone (Cliff Formation)
Limestone (predominantly CaCO3 as calcite)
Sedimentary
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with iron oxide and other mineral impurities
sedimentary (chemical/biological origin)
Gneiss (Metamorphic Rock)
Gneiss
metamorphic
Sea Bean (Hamburger Bean)
Mucuna sloanei
organic/biological specimen