Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
mineral
Category
Marble
Browse marble specimens identified by the Rock Identifier community.
Glauconitic Sandstone
Glauconitic arenite (contains (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Fossil Coral (Favosites)
Favosites (Order: Tabulata, Phylum: Cnidaria)
sedimentary
Limestone
Calcareous Sedimentary Rock (CaCO3)
sedimentary
Mother of Pearl (Nacre)
Aragonite (CaCO3) with Organic Matrix
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Olivine (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4
mineral
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
mineral
Peridotite (Olivine/Peridot)
Peridotite: (Mg,Fe)2SiO4 (Olivine-rich ultramafic rock)
igneous
Celadonite in Basalt (Green Earth)
Celadonite (K(Mg,Fe2+)(Fe3+,Al)Si4O10(OH)2)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Black Pearl (Tahitian or Irradiated Type)
Organic gemstone (Calcium Carbonate with Conchiolin Binding)
mineraloid
Glauconitic Sandstone
Glauconitic Sandstone with high Glauconite concentration ((K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Fossilized Shell in Limestone
Bivalve fossil (CaCO3) in Carbonate Sedimentary Rock
sedimentary
Olivine in Basalt (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4 (Mineral) / Scoriaceous Basalt (Host Rock)
igneous
Olivine in Basalt
Peridotite / Forsterite ((Mg,Fe)2SiO4)
igneous
Microcrystalline Limestone Pebble
Carbonate sedimentary rock (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Northern Shoveler Duck (Note: This is a biological specimen, not a rock)
Spatula clypeata
not a rock (biological/ornithological)
Olivine (Peridot)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
mineral
Glauconitic Sandstone
Greensand (Glauconite-bearing sandstone)
sedimentary
Olivine in Basalt matrix
Peridotite (Mg, Fe)2SiO4
igneous
Peridotite (Pyroxenite/Serpentinized Dunite)
Ultramafic Rock (consisting primarily of Olivine and Pyroxene)
igneous
Pearl (in a decorative hair comb setting)
Calcium carbonate (CaCO3) primarily as Aragonite, bonded with Conchiolin
Organic Mineraloid
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Olivine (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4
mineral
Olivine (Peridot when gem-quality)
Olivine Group (Magnesium Iron Silicate, (Mg,Fe)2SiO4)
mineral
Glauconitic Sandstone
Glauconitic Sandstone (complex silicate formula: (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
sedimentary
Chert (often called Flint or Jasper depending on color)
Chert (SiO2 - Microcrystalline or Cryptocrystalline Quartz)
sedimentary
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
mineral
Fossiliferous Limestone
Calcium Carbonate - CaCO3
sedimentary
Olivine Diabase Porphyry
Porphyritic Olivine-Bearing Diabase (Micro-Gabbro)
igneous
Olivine (Peridot)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
mineral
Limestone with Calcite Veins
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
sedimentary
Limestone
Calcareous Sedimentary Rock (CaCO3)
sedimentary
Precious Coral
Corallium rubrum (Calcium carbonate with trace carotene)
Organic gemstone / Sedimentary mineraloid
Glauconite (Sandstone or Shale)
Glauconite (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
sedimentary
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
mineral
Mother of Pearl (Nacre)
Aragonite (layered with organic polymers), CaCO3
mineral
Olivine (Peridot)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
mineral
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with fossil inclusions
sedimentary