Slag Glass (Cullet)
Amorphous Silica / Glass residue
Category
Browse man made metamorphic style composite specimens identified by the Rock Identifier community.
Slag Glass (Cullet)
Amorphous Silica / Glass residue
Ferrosilicon Slag (Industrial Vitrified Glass)
Vitreous Silicate Residue
Synthetic Costume Glove (Paws)
Polyethylene terephthalate (Polyester) & Polyurethane blend
Slag
Anthropogenic Vitrification Product / Silicate Slag
Quartz
Silicon Dioxide (SiO₂)
Smoky Quartz
Smoky Quartz (SiO2)
Lapis Lazuli
A metamorphic rock primarily composed of lazurite (Na,Ca)8[(S,SO4,Cl)2|(Al6Si6O24)], calcite (CaCO3), and pyrite (FeS2).
Sea Glass (Teal/Turquoise)
Amorphous Silica (SiO2) with trace metal oxides
Sea Glass (Turquoise/Aqua)
Amorphous Silica (SiO2) with transition metal dopants
Sea Glass (Frosted Glass)
Amorphous Silica (SiO2) with various metal oxide impurities
Metal Alloy (Jewelry)
Not a naturally occurring rock or mineral; likely a metal alloy for jewelry. Possible compositions include sterling silver (92.5% silver, 7.5% copper), or other silver/gold alloys.
United States Quarter Dollar
Cupronickel Clad Alloy (75% Copper, 25% Nickel over a 100% Copper core)
Green Glass Cullet / Recycled Glass
Amorphous Silicon Dioxide (SiO2) with various metal oxides
Agate (specifically, multi-colored or pastel-dyed agate)
Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).
Cullet Glass (Industrial Slag Glass)
Amorphous Silica (SiO2) with metallic oxide impurities
Red Swirl Beads (Likely Resin or Glass, simulating Red Jasper or Agate)
N/A (for the beads as pictured); Red Jasper: SiO2 (Chert variety); Red Agate: SiO2 (Chalcedony variety)
Metallic Ornament / Jewelry
N/A - This is an artificial object, not a geological specimen.
Ironstone Nodule (Ironstone Concretion)
Siderite-rich Mudstone (FeCO3) or Limonite (FeO(OH)·nH2O)
Sandstone Chert/Quartzite
Silicon Dioxide (SiO2) - Sedimentary Sandstone / Orthoquartzite
Quartz Geode
Macrocrystalline Quartz (SiO2) within a geode structure
Quartz on Chlorite Schist
Chlorite Schist (Mg,Fe)3(Si,Al)4O10(OH)2 with Quartz (SiO2)
Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone)
Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)
Likely slate fragment
Slate; fine-grained foliated metamorphic rock, commonly quartz–mica–chlorite rich
Quartzite
Quartzite
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Jasper (Mookaite style)
Jasper (Silica-rich Microcrystalline Quartz, SiO2)
Iron-stained quartz-rich rock, possibly jasper or chert
Microcrystalline quartz (SiO₂) with iron oxides/hydroxides
Rock crystal quartz fragment
Quartz (silicon dioxide, SiO₂)
Basalt
Basalt
Ruby
Corundum (Al2O3 with chromium impurities)
Granite
Granite (plutonic igneous rock)
Chalk
Micrite (primarily Calcium Carbonate, CaCO3)
Granite
Felsic Plutonic Rock
Granite with Epidote
Granite, containing quartz, feldspar, and epidote
Biotite Mica Schist
Metamorphic Rock containing Biotite K(Mg,Fe)3AlSi3O10(OH)2
Sandstone
Arenite (composed primarily of Quartz: SiO2)
Pegmatite
Igneous Pegmatite
Diabase (Dolerite)
Diabase / Dolerite
Blue glass-like tumbled specimen
Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image
Biotite (Black Mica)
K(Mg,Fe)3AlSi3O10(OH,F)2
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)