Marble
Recrystallized Calcite (CaCO3)
Category
Browse metamorphic (man made) specimens identified by the Rock Identifier community.
Marble
Recrystallized Calcite (CaCO3)
Greenstone
Metamorphic mafic rock (chlorite-actinolite-epidote schist)
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
Pyrite
Iron Sulfide (FeS2)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8) with Albite inclusions
White-and-dark marble or agate-style gemstone bead bracelet
Likely calcite-rich marble (CaCO₃) mixed with dark gray stone beads; exact material is uncertain from the photo
Rutilated Quartz
Quartz with Rutile inclusions (SiO2 with TiO2)
Nephrite Jade
Ca2(Mg,Fe)5Si8O22(OH)2
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
Quartzite
Metamorphosed Quartz Sandstone
Amethyst
Silicon Dioxide (SiO2)
Nephrite Jade
Ca2(Mg, Fe)5Si8O22(OH)2
Slate
Metamorphic pelitic rock
Lapis Lazuli
Lapis Lazuli (Complex rock consisting primarily of Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2)
Quartzite (River Pebble)
Quartzite (Mainly SiO2)
Polished dark gray stone, likely basalt or fine-grained andesite
Basalt/andesite; primarily plagioclase feldspar, pyroxene, and possibly olivine or magnetite
Amethyst (or Light Amethyst / Rose Quartz)
Quartz (Silicon Dioxide, SiO2)
Fine-grained gray stone, possibly slate
Slate (fine-grained metamorphosed mudstone); identification is uncertain from the image
Graphite
Graphite (Carbon, C)
Unakite
Altered Granite (Epidotized Granite)
Asphalt Pavement (with aggregate)
Asphalt concrete
Blue Slag Glass
Amorphous Silica (Byproduct of smelting)
Cardstock (Paper)
Cellulose (C6H10O5)n
Blue Goldstone
Aventurine Glass (SiO2 with Cobalt/Copper inclusions)
Synthetic Resin (Artificial Specimen)
Polyurethane or Polyester Resin
Slag Glass (Cullet)
Amorphous Silicon Dioxide (SiO2) with metal oxide colorants
Slag (Anthropogenic Glass/Iron byproduct)
Ferro-silicate Slag
Artisanal Glass Beads (Simulated Goldstone or Aventurine Glass)
Silicon Dioxide (SiO2) with metallic inclusions
Polished black stone carving, likely soapstone/steatite
Steatite (massive talc), Mg₃Si₄O₁₀(OH)₂; exact material cannot be confirmed from the image
Quartzite
Silica (SiO2) quartzite
Greenstone / serpentinite carving
Serpentinite, chiefly serpentine-group minerals (antigorite, lizardite, or chrysotile); exact identification requires testing
Smoky Quartz (Faceted)
Silicon Dioxide (SiO2)
Beaded gemstone bracelet, likely lapis lazuli and pale quartz/agate
Lapis lazuli: lazurite-rich rock, chiefly (Na,Ca)₈(AlSiO₄)₆(S,SO)₂; pale beads are uncertain
Blue chalcedony cabochon (probable)
Chalcedony, a cryptocrystalline variety of quartz; silicon dioxide, SiO₂
Natural freshwater pearls
Pearl (nacreous calcium carbonate; chiefly aragonite, CaCO₃)
Pyrite
Iron Sulfide (FeS2)
Blue slag glass / industrial smelter slag
Man-made iron-rich silicate slag; composition variable, commonly Fe–Ca–Mg–Al silicates with glassy phases
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
Pyrite
Iron Sulfide (FeS2)
Sea Glass
Amorphous Silicon Dioxide (SiO2)
Crackle Glass (Simulated Gemstone)
Amorphous Solid (SiO2)