Man Made Composite

Tumbled opalite (likely man-made glass)

Opalite, a trade name for opalescent glass; not natural opal

Opalite (likely imitation opal glass)

Man-made opalescent glass; not a natural mineral (often sold as opalite)

Blue glassy-looking specimen, possibly dyed or coated mineral

Not identifiable from the photograph; possibilities include dyed quartz or glassy slag, but composition cannot be established visually.

Milky quartz (rough quartz fragment)

Quartz, silicon dioxide (SiO₂)

Chert Concretion

Chert (Microcrystalline Quartz, SiO2)

Crescent Pebble

Weathered Quartzite or Sandstone Fragment

Polished brown jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide and other mineral inclusions

Likely tumbled or cut quartz/chalcedony fragment

Silicon dioxide (SiO₂), probably microcrystalline quartz or quartz

Boxwork or Septarian Concretion

Septarian nodule / Boxwork weathering

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂), likely milky quartz

Clear quartz sphere

Quartz (silicon dioxide, SiO₂)

Sandstone (with concrete/human-made layer)

Clastic Sedimentary Rock (primarily Quartz/Feldspar grains)

Mystic Topaz

Aluminum Silicate Fluoride Hydroxide (Al2SiO4(F,OH)2) with metallic film coating

Opalite

Synthetic Glass (Hydrated Crystalline Silicon Dioxide simulation)

Obsidian (Blue)

Volcanic Glass (SiO2)

Blue Cracked Quartz (Dyed Fire Crackle Quartz)

Silicon Dioxide (SiO2) with synthetic dye

Slag

Metallurgical Slag

Pink Quartz / Sea Glass

Silicon Dioxide (SiO2)

Clear quartz crystal (likely)

Quartz, silicon dioxide (SiO₂)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂)

White sea glass (naturally frosted glass fragment)

Man-made silicate glass, typically soda-lime glass; not a mineral or rock

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)

Goldstone

Aventurine glass (Synthetic glass with copper inclusions)

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

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

Quartz, silicon dioxide (SiO₂)

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

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

Possible obsidian or slag glass

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

Fluorite (Polished Point/Tower)

Calcium Fluoride (CaF2)

Sea Glass

Amorphous silicon dioxide (SiO2) - Man-made glass tumbled by nature

Blue Goldstone

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

Clear quartz tumbled stone

Quartz (silicon dioxide, SiO₂)

Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)

Ferrochrome Slag

Anthropogenic slag (Fe-Cr alloy waste)