Not A Natural Rock (Man Made Composite)

Granite

Phaneritic Igneous Rock (composed mostly of Quartz, Alkali Feldspar, and Plagioclase)

Basalt

Extrusive Igneous Rock

Diamond

Carbon (C)

Slag Glass (Cullet)

Amorphous Silica / Glass residue

Diamond (Cut jewelry specimen)

Diamond (pure Carbon, C)

Ruby in Matrix

Corundum (Al2O3)

Red agate bead (likely dyed or treated)

Agate, a microcrystalline variety of quartz; SiO₂

Dragon Vein Agate (Dyed/Treated)

Agate (SiO2)

Yellow faceted gemstone, likely citrine or yellow sapphire

Uncertain; probable quartz (SiO₂) or corundum (Al₂O₃)

Fossilized gastropod (likely nerite or related sea snail)

Gastropoda; shell composed originally of aragonite/calcite, commonly replaced or infilled by calcite

Fired Clay Brick (Anthropic Rock substitute)

Anthropogenic polycrystalline ceramic (predominantly Mullite and Quartz: Al6Si2O13 + SiO2)

Diamond (or Diamond Simulant)

Carbon (C) or Cubic Zirconia (ZrO2)

Brecciated Jasper

Brecciated Jasper (Microcrystalline Quartz / SiO2)

Diamond (in Jewelry)

Carbon (C)

Blue chalcedony cabochon (probable)

Chalcedony, a cryptocrystalline variety of quartz; silicon dioxide, SiO₂

Tumbled greenstone (likely serpentinite or green jasper)

Serpentinite, commonly dominated by serpentine-group minerals (Mg₃Si₂O₅(OH)₄); exact identification requires testing

Polished blue gemstone bead bracelet, likely aquamarine

Aquamarine, blue variety of beryl (Be₃Al₂Si₆O₁₈); identification from the image is uncertain

Lapis lazuli and green-blue chalcedony jewelry

Lapis lazuli: lazurite-bearing metamorphic rock, chiefly lazurite (Na₃Ca(Al₃Si₃O₁₂)S) with calcite and pyrite; second stone: likely chrysoprase or green-blue chalcedony (microcrystalline quartz, SiO₂)

Crushed Limestone

Calcium Carbonate (CaCO3)

Diamond (Cut and Polished)

Diamond (pure Carbon, C)

Diamond

Carbon (C)

Black tumbled stone, possibly obsidian

Obsidian (natural volcanic glass; composition varies, typically silica-rich)

Red-and-brown agate bead bracelet

Agate, a microcrystalline variety of quartz (SiO₂), likely colored chalcedony/carnelian

Conglomerate

Conglomerate (Clastic Sedimentary Rock)

Weathered conglomeratic river cobble

Polymictic conglomerate or breccia, likely matrix-supported

Blue Goldstone

Aventurine Glass

Iron-Nickel Meteorite (Possible Chondrite or Oxidized Iron)

Siderite (Nickel-Iron) or Chondrite (Si/Fe composite)

Polished pietersite-like brecciated jasper

Silicified chalcedony/jasper aggregate, primarily SiO₂; exact material uncertain from image

Basalt

Basalt

Polished basalt or basaltic river pebble

Basalt; fine-grained plagioclase–pyroxene rock, possibly containing olivine

Amethyst gemstone ring

Quartz, purple variety — SiO₂

Diamond

Native Carbon (C)

Diamond (faceted)

Diamond (Pure Carbon, C)

Faceted gemstone in a jewelry setting

Indeterminate from image; likely quartz, cubic zirconia, or another transparent faceted stone

Blue tumbled glass or dyed stone (uncertain)

Unidentified; appearance is consistent with blue glass, but a blue mineral such as dyed quartz cannot be ruled out from the photo

Orgonite Pyramid (containing Amethyst and mixed minerals)

Silicon Dioxide (SiO2) in synthetic resin

Diamond

Carbon (C)

Flint (gray chert)

Microcrystalline quartz (SiO₂), a variety of chert

Clear-stone silver-tone teardrop earring

The stones may be colorless quartz or glass; the image does not allow reliable identification. Metal setting appears silver-tone.

Tumbled greenstone / serpentinite (probable)

Serpentinite, chiefly Mg-rich serpentine minerals (antigorite, lizardite, chrysotile), possibly mixed with chlorite, magnetite, or carbonate

Probable amber fragment

Amber (fossilized plant resin; chiefly amorphous organic resin, commonly dominated by succinite)

Polished serpentine-rich stone (likely serpentine jasper or “rainforest jasper”)

Serpentine-group minerals, chiefly antigorite/lizardite, with iron oxides and silica-rich rock matrix