Man Made Object (Simulant)

Howlite

Howlite (Calcium borosilicate hydroxide, Ca2B5SiO9(OH)5)

Blue chalcedony bead necklace

Chalcedony, microcrystalline quartz (SiO₂), commonly blue-dyed or blue-gray natural chalcedony

Pearl

Calcium Carbonate (Aragonite/Calcite) with Conchiolin

Diamond

Carbon (C)

Likely rough pink feldspar or rose quartz

Most likely microcline feldspar (KAlSi₃O₈) or rose quartz (SiO₂)

Blue sapphire ring

Corundum (aluminum oxide, Al₂O₃), likely heat-treated sapphire

Polished black obsidian

Volcanic glass; primarily rhyolitic SiO₂, with minor iron, magnesium, and other trace elements

Botryoidal chalcedony with quartz vug

Microcrystalline quartz, SiO₂ (chalcedony), with a drusy quartz-lined cavity

Diamond (or Cubic Zirconia simulant)

Carbon (C) or Zirconium Dioxide (ZrO2)

Terrazzo (with Marble and Granite fragments)

Cementitious or resinous composite containing Calcium Carbonate (CaCO3) and Silicates

Blue glass-like heart pendant, likely synthetic blue spinel or colored glass

Unconfirmed; possibly synthetic spinel (MgAl₂O₄) or cobalt-colored glass

Serpentinite

Serpentinite (composed primarily of Serpentine minerals: Mg3Si2O5(OH)4)

Pink/red faceted gemstone, likely synthetic corundum or glass imitation

Corundum (Al₂O₃), ruby/sapphire variety; exact identification requires testing

Diamond (or Cut Gemstone / Cubic Zirconia)

Carbon (C)

Tumbled purple chalcedony or low-grade amethyst bead bracelet

Chalcedony (microcrystalline SiO₂), possibly quartz/amethyst; composition is SiO₂

Likely polished dark gemstone cabochon

Indeterminate; possibly black chalcedony/agate, obsidian, or glass imitation

Fossilized bivalve shell

Bivalvia indeterminate; likely a fossil clam or cockle

Red Jasper Cube

SiO2 (microcrystalline quartz)

Worn River Pebble with Fossil Indentation

Sedimentary Rock with Fossil Infill

Red-and-brown agate bead bracelet

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

Goldstone (blue-goldstone–style glass) beads

Artificial aventurine glass, typically silica glass with copper inclusions; not a natural mineral

Faceted colorless gemstone, likely diamond

Diamond (crystalline carbon, C)

Dyed howlite or turquoise imitation

Howlite: Ca₂B₅SiO₉(OH)₅; turquoise: CuAl₆(PO₄)₄(OH)₈·4H₂O

Diamond ring

Diamond (crystalline carbon, C)

River Pebble (likely Quartzite or Chert)

Sedimentary Clast (Silicon Dioxide dominant)

Blue calcite sphere

Calcite (CaCO₃), commonly blue-calcite variety

Fossilized shell or coral fragment

Indeterminate biogenic carbonate; likely calcite/aragonite (CaCO₃)

Stone bead bracelet

Unidentified polished natural-stone beads; possibly wood-grain jasper, agate, or serpentine

Flint or chert, possibly a knapped stone tool

Microcrystalline quartz (SiO₂), commonly chalcedony with possible carbonaceous impurities

Unable to identify - Image contains non-geological items

Likely iron-rich concretion or weathered rock pebble

Uncertain from the image; possibly an iron-oxide-cemented concretion (goethite/hematite)

Cubic Zirconia (Simulated Diamond)

Zirconium Dioxide (ZrO2)

Carved labradorite fish

Labradorite, calcium-rich plagioclase feldspar (approximately (Ca,Na)(Al,Si)₄O₈)

Clear faceted gemstone, likely cubic zirconia

Synthetic zirconium dioxide (ZrO₂), probably cubic zirconia; exact identification requires testing

Diamond ring

Diamond, crystalline carbon (C), likely a faceted mounted stone

Faceted colorless gemstone, likely cubic zirconia or diamond

Most likely synthetic cubic zirconia (ZrO₂); diamond (C) is a less certain alternative

Painted River Rock (likely Quartzite or Granite)

Quartzite or Granitic Gneiss (painted)

Siltstone or Limestone Beach Pebble

Siltstone / Micritic Limestone

Quartzite Pebble

Metamorphosed Quartz Sandstone (SiO2)

Tanzanite earrings

Tanzanite, blue-violet zoisite (Ca₂Al₃(SiO₄)₃(OH))

Polished brecciated jasper pendant

Jasper, an opaque microcrystalline variety of chalcedony (mostly SiO₂), with iron-oxide staining and likely brecciation

Colorless faceted gemstone, likely cubic zirconia

Synthetic cubic zirconia (ZrO₂), tentative; possibly diamond or synthetic moissanite