Rock Identifier

Category

Synthetic Polymer (Polylactic Acid)

Browse synthetic polymer (polylactic acid) specimens identified by the Rock Identifier community.

Learn about Synthetic Polymer (Polylactic Acid) in the encyclopedia

Yttrium Aluminum Garnet

Yttrium Aluminum Garnet

Zincite

Opalite

Lead Feldspar

Dolomite

Zircon

Orange Calcite

Polished orange calcite point (Calcite (CaCO₃), likely honey/orange calcite) — mineral

Polished orange calcite point

Calcite (CaCO₃), likely honey/orange calcite

Weathered sandstone (probable) (Quartz-rich sandstone; mainly SiO₂ with feldspar and lithic grains) — sedimentary

Weathered sandstone (probable)

Quartz-rich sandstone; mainly SiO₂ with feldspar and lithic grains

Fossilized coral (likely honeycomb or branching coral) (Fossil coral; probable Scleractinia or Tabulata, composition mainly microcrystalline CaCO₃) — fossil

Fossilized coral (likely honeycomb or branching coral)

Fossil coral; probable Scleractinia or Tabulata, composition mainly microcrystalline CaCO₃

Fossiliferous Limestone (Calcium Carbonate (CaCO3) with Bioclasts) — sedimentary

Fossiliferous Limestone

Calcium Carbonate (CaCO3) with Bioclasts

Coral Rock (Coquina) (Biogenic Limestone (Calcium Carbonate - CaCO3)) — sedimentary

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Blue calcite cluster (Calcite (calcium carbonate, CaCO₃)) — mineral

Blue calcite cluster

Calcite (calcium carbonate, CaCO₃)

Limestone (CaCO3 (principally Calcite)) — sedimentary

Limestone

CaCO3 (principally Calcite)

Mixed polished river stones (Likely quartz, quartzite, chert/jasper, and possibly limestone or marble) — mineral

Mixed polished river stones

Likely quartz, quartzite, chert/jasper, and possibly limestone or marble

Orange calcite (Calcite (CaCO₃), likely honey/orange calcite) — mineral

Orange calcite

Calcite (CaCO₃), likely honey/orange calcite

Limestone (Calcium carbonate (CaCO3)) — sedimentary

Limestone

Calcium carbonate (CaCO3)

Blue calcite (Calcite (CaCO₃), blue variety) — mineral

Blue calcite

Calcite (CaCO₃), blue variety

Limestone (Carved Statue) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Carved Statue)

Calcium Carbonate (CaCO3)

Limestone (River Pebble) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (River Pebble)

Calcium Carbonate (CaCO3)

Rounded gray pebble (Indeterminate; likely a water-worn silicate or carbonate pebble) — sedimentary

Rounded gray pebble

Indeterminate; likely a water-worn silicate or carbonate pebble

Chalky limestone (Micritic calcite limestone; predominantly CaCO₃) — sedimentary

Chalky limestone

Micritic calcite limestone; predominantly CaCO₃

Turquoise (CuAl6(PO4)4(OH)8·4H2O) — mineral

Turquoise

CuAl6(PO4)4(OH)8·4H2O

Turquoise (Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)) — mineral

Turquoise

Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)

Limestone (Calcite (CaCO3)) — sedimentary

Limestone

Calcite (CaCO3)

Amber (Fossilized Tree Resin (Amorphous Hydrocarbon)) — Mineral

Amber

Fossilized Tree Resin (Amorphous Hydrocarbon)

Diamond (Rough) (Diamond (Carbon, C)) — Mineral

Diamond (Rough)

Diamond (Carbon, C)

Ruby (Corundum (mineral species), variety: Ruby (Al2O3 with Cr3+ as the chromophore)) — Mineral

Ruby

Corundum (mineral species), variety: Ruby (Al2O3 with Cr3+ as the chromophore)

Moonstone (bead form) (Potassium Aluminum Silicate (KAlSi3O8) - a variety of Orthoclase Feldspar) — Mineral

Moonstone (bead form)

Potassium Aluminum Silicate (KAlSi3O8) - a variety of Orthoclase Feldspar

Amazonite (KAlSi3O8 (Potassium Feldspar, variety of Microcline)) — Mineral

Amazonite

KAlSi3O8 (Potassium Feldspar, variety of Microcline)

Blue Tiger's Eye (Riebeckite (crocidolite variety)) — Mineral

Blue Tiger's Eye

Riebeckite (crocidolite variety)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Green glassy mineral specimen, likely rough emerald or green fluorite (Tentatively beryl (Be₃Al₂Si₆O₁₈), emerald variety; synthetic/man-made glass cannot be excluded from the photograph) — mineral

Green glassy mineral specimen, likely rough emerald or green fluorite

Tentatively beryl (Be₃Al₂Si₆O₁₈), emerald variety; synthetic/man-made glass cannot be excluded from the photograph

Calcite (Calcium Carbonate (CaCO3)) — mineral

Calcite

Calcium Carbonate (CaCO3)

Kidney Stone (Medical Specimen) (Calcium oxalate monohydrate (Whewellite) / CaC2O4·H2O) — Mineral (Biogenic)

Kidney Stone (Medical Specimen)

Calcium oxalate monohydrate (Whewellite) / CaC2O4·H2O

Mineral (Biogenic)

Yellow Calcite (Calcite (Calcium Carbonate, CaCO3)) — mineral

Yellow Calcite

Calcite (Calcium Carbonate, CaCO3)

Malachite-bearing Rock (Cu2CO3(OH)2) — mineral

Malachite-bearing Rock

Cu2CO3(OH)2

Likely weathered river pebble (Indeterminate lithology; possibly fine-grained sandstone, siltstone, or chert) — sedimentary

Likely weathered river pebble

Indeterminate lithology; possibly fine-grained sandstone, siltstone, or chert

Peacock Ore (Bornite or Iridescent Chalcopyrite) (Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with oxidation) — mineral

Peacock Ore (Bornite or Iridescent Chalcopyrite)

Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with oxidation

Likely quartz-rich metamorphic rock (quartzite or quartz-veined schist) (Quartzite/siliceous schist; chiefly quartz (SiO₂), with probable mica and iron-oxide staining) — metamorphic

Likely quartz-rich metamorphic rock (quartzite or quartz-veined schist)

Quartzite/siliceous schist; chiefly quartz (SiO₂), with probable mica and iron-oxide staining

Green Calcite (Calcium Carbonate (CaCO3)) — mineral

Green Calcite

Calcium Carbonate (CaCO3)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Limestone (with possible Crinoid or Fossil Impression) (Calcium Carbonate (CaCO3) / Calcite) — sedimentary

Limestone (with possible Crinoid or Fossil Impression)

Calcium Carbonate (CaCO3) / Calcite

Limestone (Sedimentary rock primarily composed of Calcite (CaCO3)) — sedimentary

Limestone

Sedimentary rock primarily composed of Calcite (CaCO3)

Fossiliferous Limestone (Biomicrite / Fossiliferous Limestone (CaCO3)) — fossil

Fossiliferous Limestone

Biomicrite / Fossiliferous Limestone (CaCO3)

Fossiliferous Limestone (CaCO3 (with biological inclusions)) — sedimentary

Fossiliferous Limestone

CaCO3 (with biological inclusions)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Limestone (Calcareous sedimentary rock (CaCO3)) — sedimentary

Limestone

Calcareous sedimentary rock (CaCO3)

Yellow Calcite (Calcium Carbonate, CaCO3) — mineral

Yellow Calcite

Calcium Carbonate, CaCO3