Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
mineral
Category
Synthetic Polymer (Polylactic Acid)
Browse synthetic polymer (polylactic acid) specimens identified by the Rock Identifier community.
Sulfur
Native Sulfur (S8)
mineral
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
mineral
Fluorite (Purple Fluorite in Matrix)
Fluorite (Calcium Fluoride, CaF2)
mineral
Rhodochrosite
Manganese Carbonate (MnCO3)
mineral
Dolomite
Dolomite (CaMg(CO3)2)
Mineral
Marble
Marble (primarily Calcite, CaCO3 or Dolomite, CaMg(CO3)2)
Metamorphic Rock
Fluorite
Fluorite (Calcium Fluoride - CaF2)
mineral
Pink Granite
Phaneritic Acidic Plutonic Rock (primarily K-feldspar, quartz, and plagioclase)
Igneous
Limestone (Cliff Formation)
Limestone (predominantly CaCO3 as calcite)
Sedimentary
Granite
Phaneritic Acidic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
igneous
Fluorite
Calcium Fluoride (CaF2)
mineral
Calcite
Calcite (CaCO 3)
Mineral
Chert (or Flint)
Chert (cryptocrystalline quartz), SiO2
Sedimentary
Chalcedony or Chert/Jasper with secondary mineral staining
SiO2 (for chalcedony/quartz) with possible secondary copper minerals (e.g., CuSiO3·nH2O for chrysocolla, Cu2(CO3)(OH)2 for malachite) or iron oxides/hydroxides.
Mineral, potentially a rock with chalcedony/jasper.
Marble
Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).
Metamorphic Rock
Calcite
Calcite (Mineral, Calcium Carbonate - CaCO3)
Mineral
Hand-Drawn Trading Card (Amateur Artwork)
Cellulose-based substrate with wax/graphite/ink deposit (n/a for minerals)
Organic/Synthetic Composite (Paper and Pigment)
Iron Meteorite
Iron-nickel alloy (primarily kamacite and taenite)
Mineral/Rock (Extraterrestrial Origin)
Pyrite
Pyrite (FeS2)
Mineral
Aragonite (variety 'Flos Ferri')
Aragonite (CaCO3)
Mineral
Talc
Talc (Mg₃Si₄O₁₀(OH)₂)
Mineral
Chert (varietal known as Jasper or Flint)
Silicon Dioxide (SiO2)
Sedimentary Rock
Chalk
Calcareous Ooze (composed primarily of coccoliths)
Sedimentary Rock
Aragonite
Aragonite (CaCO3)
mineral
Coquina
Coquina (a type of limestone)
Sedimentary
Quartz (vein quartz)
SiO2 (Silicon Dioxide)
Mineral
Pyrite
Pyrite (Iron Disulfide), FeS2
Mineral
Travertine (used in construction, not a 'specimen' in situ)
Travertine
Sedimentary
Chert (varietal: Jasper or Flint likely, but definitive identification is difficult from image)
SiO₂ (silicon dioxide)
Sedimentary
Banded Calcite or Travertine
Calcium Carbonate (CaCO3)
Sedimentary
Malachite
Malachite (Cu2CO3(OH)2)
mineral
Malachite
Malachite (Cu2(CO3)(OH)2 - a copper carbonate hydroxide mineral)
Mineral
Fluorite Bracelet (light green beads) and possibly Lavender Jadeite (purple bead)
Fluorite: CaF₂ (Calcium Fluoride); Jadeite: NaAlSi₂O₆ (Sodium Aluminum Silicate)
Mineral for Fluorite; Mineral/Rock for Jadeite (as it's often a rock composed primarily of jadeite mineral)
Fluorite and Rose Quartz
Fluorite (CaF2), Rose Quartz (SiO2)
Mineral
Quartzite
Quartzite
Metamorphic
Crushed Limestone
Calcium Carbonate (CaCO3)
Sedimentary
Chert (or Flint)
Chert (microcrystalline or cryptocrystalline quartz, SiO2)
Sedimentary
Sodalite
Sodalite, Na8(Al6Si6O24)Cl2
Mineral
Unidentifiable Rock Fragment
Uncertain
Banded Jasper
Silicon Dioxide (SiO2)
Mineral/Sedimentary Rock (as a cryptocrystalline variety of quartz)
Chert (Jasper-like)
SiO2 (Cryptocrystalline Quartz)
Sedimentary