Travertine
Travertine (CaCO3 - Calcium Carbonate)
sedimentary
Category
Mineral, Often A Rock Given Its Aggregate Nature
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
Learn about Mineral, Often A Rock Given Its Aggregate Nature in the encyclopedia
View all →
Jasper Pendant
Chalcedony (Quartz) - SiO2
Mineral/Sedimentary
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and organic impurities
sedimentary
Honey Calcite (Yellow Calcite)
Calcium Carbonate (CaCO3)
mineral
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Alabaster
Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)
sedimentary
Diamond
Diamond (carbon allotrope), C (chemical formula)
Mineral
Red Jasper (Mookaite style)
Silicon Dioxide (SiO2) with iron oxide impurities
sedimentary
Agate Geode
Silicon Dioxide (SiO2) - Chalcedony / Quartz Variety
Mineral
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Cat's Eye Moonstone (Simulated/Synthetic or natural Cat's Eye Quartz/Glass)
There is no single scientific name. The appearance suggests either: Moonstone (feldspar group), Cat's Eye Quartz (SiO2), Apatite (Ca5(PO4)3(F,Cl,OH)), or most likely a synthetic material such as Fiber Optic Glass or 'Opalite' (a type of glass).
Mineral
Sandstone
Sandstone (SiO2 dominant)
sedimentary
Pyrite or Chalcopyrite specimen (Gold-colored mineral coating)
Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)
mineral
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Dendrite (Manganese Oxide Dendrites)
Psilomelane or Pyrolusite on Matrix (typically MnO2)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Chrysocolla
Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Dragon Vein Agate
Chalcedony (Quartz) - SiO2
mineral
Agate (Grey Agate Slice)
Microcrystalline Quartz (SiO2)
mineral
Quartz (River Pebble)
Quartz (Silicon Dioxide - SiO2)
mineral
Basalt River Pebble
Aphanitic Mafic Igneous Rock
igneous
Shale
Shale (clay-rich mudstone)
sedimentary
Peridot (likely, given the color and bead form)
Olivine, variety Peridot (Mg,Fe)2SiO4
Mineral
Chrysocolla
Hydrated copper silicate, (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Limestone River Pebble
Calcium carbonate (CaCO3) - micritic limestone
sedimentary
Sandstone
Sandstone (SiO2-rich clastic sedimentary rock)
sedimentary
Sandstone (Calcareous Sandstone)
Calcareous Sandstone (primarily SiO2 with CaCO3 cement)
sedimentary
Chert (Jasper) Pebble
Microcrystalline Quartz (SiO2)
sedimentary
Dyed Howlite (Purple)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
mineral
River Rock
Sedimentary clast
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Jasper (Green Jasper / River Jasper)
Silicon Dioxide (SiO2) with impurities
sedimentary
Puddingstone
Conglomerate (specifically a type of jasper conglomerate or quartz conglomerate)
Sedimentary
Blue Dyed Agate Geode
Chalcedony (cryptocrystalline Quartz), SiO2
mineral
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Copper slag or vesicular basalt with copper minerals
Industrial slag / Basaltic matrix with secondary copper minerals
igneous
Volcanic Tuff (Breccia)
Pyroclastic Tuffaceous Rock
igneous
Red Jasper
Silicon Dioxide (SiO2) with Iron Oxide inclusions
sedimentary
Conglomerate
Conglomerate
Sedimentary Rock
Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
sedimentary
Chrysoprase
Chalcedony (cryptocrystalline SiO2 variety)
Mineral
Limestone
Limestone (CaCO3)
sedimentary