Rock Identifier

Category

Synthetic Polymer (Polylactic Acid)

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

Pyrite in Shale (Iron Disulfide (FeS2) in Sedimentary Shale) — mineral

Pyrite in Shale

Iron Disulfide (FeS2) in Sedimentary Shale

mineral
Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

mineral
Pyrite (Iron Disulfide (FeS2)) — Mineral

Pyrite

Iron Disulfide (FeS2)

Mineral
Pyrite (Fool's Gold) Ore (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold) Ore

Iron Disulfide (FeS2)

mineral
Fluorite (Green Fluorite) (Calcium Fluoride (CaF2)) — mineral

Fluorite (Green Fluorite)

Calcium Fluoride (CaF2)

mineral
Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

mineral
Quartzite (Quartzite (primarily Silicon Dioxide, SiO2)) — metamorphic

Quartzite

Quartzite (primarily Silicon Dioxide, SiO2)

metamorphic
Bornite (Peacock Ore) (Bornite (Cu5FeS4)) — mineral

Bornite (Peacock Ore)

Bornite (Cu5FeS4)

mineral
Bornite (Bornite (Cu5FeS4)) — mineral

Bornite

Bornite (Cu5FeS4)

mineral
Calcite (likely a tumbled specimen) (Calcite (CaCO 3 )) — Mineral

Calcite (likely a tumbled specimen)

Calcite (CaCO 3 )

Mineral
Baltic Amber (Succinite (Polmerized conifer resin)) — mineraloid

Baltic Amber

Succinite (Polmerized conifer resin)

mineraloid
Peacock Ore (Bornite (Cu5FeS4)) — mineral

Peacock Ore

Bornite (Cu5FeS4)

mineral
Tan Brown Granite (Phaneritic Biotite-Feldspar Granite) — igneous

Tan Brown Granite

Phaneritic Biotite-Feldspar Granite

igneous
Banded Onyx (Calcite Marble) (Calcite (CaCO3) - Trap-rock or Cave Onyx) — sedimentary

Banded Onyx (Calcite Marble)

Calcite (CaCO3) - Trap-rock or Cave Onyx

sedimentary
White Chalcedony (Agate) (Silicon Dioxide (SiO2)) — mineral

White Chalcedony (Agate)

Silicon Dioxide (SiO2)

mineral
Quartzite (Quartzite (Mainly SiO2)) — metamorphic

Quartzite

Quartzite (Mainly SiO2)

metamorphic
Travertine (Calcareous Tufa (CaCO3)) — sedimentary

Travertine

Calcareous Tufa (CaCO3)

sedimentary
Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

metamorphic
Optical Calcite (Iceland Spar) (Calcite (Calcium Carbonate, CaCO3)) — mineral

Optical Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

mineral
Red Shale (Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)) — sedimentary

Red Shale

Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)

sedimentary
Limestone (specifically Fossiliferous or Crinoidal Limestone) (Calcium Carbonate (CaCO3) - Calcite Rock) — sedimentary

Limestone (specifically Fossiliferous or Crinoidal Limestone)

Calcium Carbonate (CaCO3) - Calcite Rock

sedimentary
Quartzite (River Cobble) (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite (River Cobble)

Metamorphosed Quartz Sandstone (SiO2)

metamorphic
Coquina / Fossiliferous Limestone (Coquina (composed primarily of Calcium Carbonate / CaCO3)) — sedimentary

Coquina / Fossiliferous Limestone

Coquina (composed primarily of Calcium Carbonate / CaCO3)

sedimentary
Dolomite on Prehnite (Saddle-shaped Dolomite) (Dolomite [CaMg(CO3)2] on Prehnite [Ca2Al(AlSi3O10)(OH)2]) — mineral

Dolomite on Prehnite (Saddle-shaped Dolomite)

Dolomite [CaMg(CO3)2] on Prehnite [Ca2Al(AlSi3O10)(OH)2]

mineral
Orange Quartzite (Tumbled Beach Pebble) (Quartzite (primarily SiO2)) — metamorphic

Orange Quartzite (Tumbled Beach Pebble)

Quartzite (primarily SiO2)

metamorphic
Malachite (Malachite (Cu2CO3(OH)2)) — mineral

Malachite

Malachite (Cu2CO3(OH)2)

mineral
Blue Celestite (Celestine) (Strontium sulfate (SrSO4)) — mineral

Blue Celestite (Celestine)

Strontium sulfate (SrSO4)

mineral
Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

metamorphic
Bornite (Peacock Ore) (Bornite (Cu5FeS4)) — mineral

Bornite (Peacock Ore)

Bornite (Cu5FeS4)

mineral
Onyx (Black Onyx) (Silicon Dioxide (SiO2)) — mineral

Onyx (Black Onyx)

Silicon Dioxide (SiO2)

mineral
Banded Calcite (often sold as Onyx) (Calcite (Calcium Carbonate, CaCO3)) — sedimentary

Banded Calcite (often sold as Onyx)

Calcite (Calcium Carbonate, CaCO3)

sedimentary
Quartzite (Quartzite (Primary mineral: Quartz, SiO2)) — metamorphic

Quartzite

Quartzite (Primary mineral: Quartz, SiO2)

metamorphic
Malachite (Copper carbonate hydroxide [Cu2CO3(OH)2]) — Mineral

Malachite

Copper carbonate hydroxide [Cu2CO3(OH)2]

Mineral
Fossiliferous Limestone (Gritstone/Marl) (CaCO3 (Calcium Carbonate) with Fossil Inclusions) — sedimentary

Fossiliferous Limestone (Gritstone/Marl)

CaCO3 (Calcium Carbonate) with Fossil Inclusions

sedimentary
Fossilized Coral (Honeycomb Coral) (Favosites (extinct genus of tabulate corals), CaCO3 (Calcium Carbonate)) — sedimentary

Fossilized Coral (Honeycomb Coral)

Favosites (extinct genus of tabulate corals), CaCO3 (Calcium Carbonate)

sedimentary
Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

metamorphic
Howlite (Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)) — mineral

Howlite

Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)

mineral
Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

metamorphic
Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

metamorphic
Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

mineral
Sulfur (Sulfur (S8)) — mineral

Sulfur

Sulfur (S8)

mineral
Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

mineral