Sedimentary (If Natural Jasper) Or Artificial (If Slag)

Jasper (Multi-colored) / Sea Glass Slag

Silicon Dioxide (SiO2) with impurities of Iron Oxide

Slag

Anthropogenic silicate slag

Blue slag glass or dyed glass-like industrial material

Amorphous silicate glass; likely copper-bearing blue slag, but possibly colored man-made glass

Iron Slag

Anthropogenic Vitreous Silicate (Byproduct of Smelting)

Dyed Imperial Jasper

SiO2 (Silicon Dioxide)

Slag (Industrial Glass)

Artificial Vitreous Silicate

Dalmatian Jasper (Dyed Blue)

Peralkaline Rock with Arfvedsonite and Blue Dye

Cullet Glass / Slag Glass

Amorphous silica glass

Smelter Slag

Anthropogenic Silicate Slag

Dalmatian Stone

Peralkaline igneous rock containing quartz, feldspar, and arfvedsonite

Industrial slag (iron/copper smelting slag)

Multiphase vitreous metallurgical slag; commonly iron-silicate glass with metal-oxide and metallic inclusions

Vesicular volcanic scoria (likely weathered basaltic scoria)

Scoria; chiefly vesicular basalt, composed mainly of plagioclase, pyroxene, and iron-rich glass

Black volcanic glass (likely obsidian)

Obsidian; predominantly rhyolitic volcanic glass composed chiefly of amorphous SiO₂

Green obsidian (likely molded or heat-treated glass-like specimen)

Volcanic glass; predominantly rhyolitic composition (silica-rich amorphous SiO₂)

Blue slag-like mineral specimen, possibly bornite or chalcopyrite

Tentatively bornite (Cu5FeS4) or iridescent chalcopyrite (CuFeS2)

Slag (Industrial Byproduct)

Anthropogenic Vitreous Silicate material

Likely polished black-and-white stone fragment

Indeterminate from image; possibly tourmalinated quartz, black-and-white jasper, or coated stone

Painted Rock

Rock coated with synthetic acrylic paint

Purple Dyed Dalmatian Stone

Dyed Peralkaline Trachyte

Mixed Tumbled Gemstones

Various silicate and oxide minerals

Blue slag glass / industrial glass fragment

Artificial silicate glass, composition variable; likely copper- or cobalt-colored furnace slag

Asphalt Conglomerate

Artificial Bituminous Conglomerate

Purple Agate

Silicon dioxide (SiO2)

Likely basalt fragment

Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine

Dyed Quartz Geode

Silicon Dioxide (SiO2) with artificial pigment

Dyed Agate

Silicon Dioxide (SiO2)

Dyed Magnesite (or Howlite)

Magnesium carbonate (MgCO3) / Calcium borosilicate hydroxide

Painted Garden Rock

Coated Siltstone or Mudstone

Red-and-blue jasper (likely ocean jasper or dyed/polished jasper)

Microcrystalline quartz, chiefly SiO₂; jasper is an opaque chalcedony variety colored by iron oxides and other impurities

Obsidian (likely blue-sheen or coated obsidian)

Volcanic glass; primarily rhyolitic silica glass (SiO₂-rich, noncrystalline)

Dyed Agate

Silicon dioxide (SiO2) with artificial colorant

Tumbled red jasper

Jasper, microcrystalline quartz (SiO₂) colored mainly by iron oxides

Concrete / Conglomerate (Man-made)

Artificial Conglomerate (Cementitious Composite)

Tumbled brown jasper / chert

Microcrystalline quartz (SiO₂), commonly called jasper or brown chert

Polished leopard jasper (likely ocean jasper)

Silicified microcrystalline quartz/chalcedony; mainly SiO₂ with iron-oxide inclusions

Dyed Agate

Silicon dioxide (SiO2)

Ferrochrome Slag

Anthropogenic silicate/oxide glass (Complex silicate matrix with Cr-Fe-Si inclusions)

Dyed Agate

Silicon Dioxide (Chalcedony), SiO2

Possible flint or slag fragment

Microcrystalline quartz (chalcedony), or iron-rich industrial slag

Scoria (vesicular basalt)

Scoria; vesicular mafic volcanic rock, commonly basaltic in composition

Quartz Pebble (Chalcedony / Agate)

Silicon Dioxide (SiO2)

Slag (Industrial Glass/Metal Waste)

Artificial silicate/ferro-silicate byproduct