Mineraloid (Man Made)

Concrete

Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)

Sandstone (with man-made markings)

Arenite (composed primarily of Quartz, SiO2)

Precious Coral (Red Coral)

Corallium rubrum (Calcium Carbonate, CaCO3)

Clear quartz crystal (likely)

Quartz, silicon dioxide (SiO₂)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Diamond / Clear Quartz / Glass paste

Carbon (Diamond) / Silicon Dioxide (Quartz)

Opalite

Synthetic Glass (Simulated Moonstone/Opal)

Diamond (or Cubic Zirconia)

Carbon (C) or Zirconium Dioxide (ZrO2)

Rock crystal quartz fragments

Quartz (silicon dioxide, SiO₂)

Cherry Quartz with Rose Quartz

Crystalline Quartz (SiO2) with glass-based synthetic components

Blue Goldstone

Aventurine Glass

Strawberry Quartz

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

Quartz (likely milky quartz or quartz glass-like fragment)

Quartz, silicon dioxide (SiO₂)

Black tumbled stone, possibly obsidian

Obsidian (volcanic glass; predominantly SiO₂), identification uncertain from image

Rounded graywacke or sandstone cobble

Lithified clastic sandstone; likely quartz–feldspar–lithic grain aggregate in a silica or calcite matrix

Faceted clear gemstone, likely quartz or glass imitation

Most likely quartz (SiO₂); exact identification requires refractive-index and hardness tests

Clear quartz crystal (likely)

Quartz, silicon dioxide (SiO₂)

Polished dendritic agate or jasper

Microcrystalline quartz (SiO₂), likely chalcedony with iron/manganese dendrites

Clear quartz tumbled stone

Quartz (silicon dioxide, SiO₂)

Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)

Concrete with Aggregate

Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)

Ferrochrome Slag

Anthropogenic slag (Fe-Cr alloy waste)

Goldstone (Red)

Aventurine Glass (Cupriferous glass)

Fluorite (Polished Point/Tower)

Calcium Fluoride (CaF2)

Possible obsidian or slag glass

Volcanic glass, primarily SiO₂; alternatively industrial iron-rich glassy slag

Cubic Zirconia (Simulated Diamond)

Cubic Zirconia (ZrO2)

Blue Glass or Slag Glass

Amorphous Silica (Anthropogenic Glass)

Blue-dyed tumbled quartz or glass imitation

Quartz (SiO₂), appearance possibly enhanced with blue dye; identity uncertain from image

Blue Goldstone

Man-made glass with suspended copper, cobalt, or manganese particles

Polished gemstone tower assortment

Primarily quartz varieties and simulants; apparent amethyst (SiO₂), rose quartz (SiO₂), clear quartz (SiO₂), fluorite (CaF₂), sodalite, malachite, and possibly dyed or composite stones

Quartz crystal (likely clear quartz)

Quartz, silicon dioxide (SiO₂)

Polished black stone, likely black obsidian

Obsidian (volcanic glass), chiefly silica-rich rhyolitic composition

Sandstone Anvil / Nutting Stone

Quartzose Sandstone (Sedimentary Rock)

Pink Tumbled Quartz (Dyed)

Silicon Dioxide (SiO2)

Dyed Crackle Quartz (Green)

Quenching-treated Quartz (Silicon Dioxide, SiO2)

Quartzite (Engineered Stone)

Silicon Dioxide (SiO2) based synthetic composite

Chert Concretion (with typical hematite/limonite staining)

Sedimentary Concretion (SiO2 with FeO(OH)⋅nH2O)

Sandstone Concretion

Clastic Sedimentary Rock (primarily SiO2 with mineral cement)

Pyrite Concretion (Grapestone)

Iron Sulfide (FeS2) Concretion

Black glassy fragment, likely obsidian or industrial glass

Volcanic glass (obsidian), chiefly amorphous SiO₂; identification uncertain from image

Pearl (Biogenic Mineraloid)

Calcium carbonate (Aragonite) and Conchiolin, CaCO3

Tumbled gray stone, likely quartz-rich pebble

Probable microcrystalline quartz/chalcedony (SiO₂), possibly gray jasper or quartzite