Rock Identifier

Category

Synthetic Or Natural Fiber

Browse synthetic or natural fiber specimens identified by the Rock Identifier community.

Amethyst (Rose-tinted variation) (Silicon Dioxide (SiO2) with trace iron impurities) — mineral

Amethyst (Rose-tinted variation)

Silicon Dioxide (SiO2) with trace iron impurities

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Granite (Granite (Silicic Plutonic Rock)) — igneous

Granite

Granite (Silicic Plutonic Rock)

Howlite (Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)) — mineral

Howlite

Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)

Sandstone (Quartzose Sandstone) (Clastic Terrigenous Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Quartzose Sandstone)

Clastic Terrigenous Sedimentary Rock (primarily SiO2)

Halite (Himalayan Pink Salt) (Halite - NaCl (Sodium Chloride)) — Mineral (Evaporite)

Halite (Himalayan Pink Salt)

Halite - NaCl (Sodium Chloride)

Mineral (Evaporite)

Magnetite (Iron(II,III) oxide (Fe3O4)) — mineral

Magnetite

Iron(II,III) oxide (Fe3O4)

Smoky Quartz (with Iron Oxidation) (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz (with Iron Oxidation)

Silicon Dioxide (SiO2)

Turquoise (Blue Howlite / Magnesite imitation) (CuAl6(PO4)4(OH)8·4H2O (for natural Turquoise); Ca2B5SiO9(OH)5 (for Howlite)) — mineral

Turquoise (Blue Howlite / Magnesite imitation)

CuAl6(PO4)4(OH)8·4H2O (for natural Turquoise); Ca2B5SiO9(OH)5 (for Howlite)

Chalk (Limestone variant) (Calcium Carbonate (CaCO3)) — sedimentary

Chalk (Limestone variant)

Calcium Carbonate (CaCO3)

Rough Corundum (Sapphire/Ruby mixture) (Corundum (Aluminum Oxide, Al2O3)) — mineral

Rough Corundum (Sapphire/Ruby mixture)

Corundum (Aluminum Oxide, Al2O3)

Citrine (Silicon Dioxide (SiO₂)) — mineral

Citrine

Silicon Dioxide (SiO₂)

Magnetite (Magnetite (Fe3O4)) — mineral

Magnetite

Magnetite (Fe3O4)

Sandstone (Ferruginous) (Arenite (with Hematite/Limonite cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (with Hematite/Limonite cement)

Diamond (or Lab-Grown Cubic Zirconia) (Carbon (C)) — mineral

Diamond (or Lab-Grown Cubic Zirconia)

Carbon (C)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Diamond (Set in jewelry) (Cubic Carbon (C)) — mineral

Diamond (Set in jewelry)

Cubic Carbon (C)

Black Pearl (Tahitian Type) (Aragonite / Conchiolin composite (CaCO3)) — mineraloid

Black Pearl (Tahitian Type)

Aragonite / Conchiolin composite (CaCO3)

Citrine (Silicon Dioxide (SiO2)) — mineral

Citrine

Silicon Dioxide (SiO2)

Shale (Fissile mudstone (Shale)) — sedimentary

Shale

Fissile mudstone (Shale)

Limonite (with goethite) (Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)) — mineral

Limonite (with goethite)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Shale (Shale (comprised mostly of clay minerals and quartz)) — sedimentary

Shale

Shale (comprised mostly of clay minerals and quartz)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine or Iron-Stained Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine or Quartzite Pebble) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine or Quartzite Pebble)

Silicon Dioxide (SiO2)

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Dyed Agate (Silicon Dioxide (SiO2) - Variety Agate / Chalcedony) — mineral

Dyed Agate

Silicon Dioxide (SiO2) - Variety Agate / Chalcedony

Basalt (Basalt (Mafic volcanic rock)) — igneous

Basalt

Basalt (Mafic volcanic rock)

Veined Limestone (Micrite) with Quartz/Calcite Veins (Calcium Carbonate (CaCO3) with Silicate or Carbonate inclusions) — sedimentary

Veined Limestone (Micrite) with Quartz/Calcite Veins

Calcium Carbonate (CaCO3) with Silicate or Carbonate inclusions

Cullet Glass (sometimes mistaken for Blue Obsidian or Slag) (Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)) — mineraloid / industrial byproduct

Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)

Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)

mineraloid / industrial byproduct

Smoky Quartz (SiO2 (Silicon Dioxide with aluminum impurities)) — mineral

Smoky Quartz

SiO2 (Silicon Dioxide with aluminum impurities)

Sandstone (Arenite (SiO2 principal)) — sedimentary

Sandstone

Arenite (SiO2 principal)

Sandstone (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone

Clastic Sedimentary Rock (primarily SiO2)

Shale (Fissile mudstone (primarily clay minerals and silt-sized quartz)) — sedimentary

Shale

Fissile mudstone (primarily clay minerals and silt-sized quartz)

Yellow Ocher / Limonite (FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)) — mineral

Yellow Ocher / Limonite

FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)

Slate (Metamorphosed Shale (Fine-grained Foliated Metamorphic Rock)) — metamorphic

Slate

Metamorphosed Shale (Fine-grained Foliated Metamorphic Rock)

Coquina (Bioclastic Limestone (Coquina)) — sedimentary

Coquina

Bioclastic Limestone (Coquina)

Shale (Shale (composition varies: primarily clay minerals and quartz)) — sedimentary

Shale

Shale (composition varies: primarily clay minerals and quartz)

Shale (Shale (Consolidated fine-grained clay/silt)) — sedimentary

Shale

Shale (Consolidated fine-grained clay/silt)

Sandstone (Arenite (SiO2 primarily)) — sedimentary

Sandstone

Arenite (SiO2 primarily)

Ruby and Diamond in Gold Setting (Corundum (Al2O3) and Diamond (C)) — mineral

Ruby and Diamond in Gold Setting

Corundum (Al2O3) and Diamond (C)