Mineraloid (Human Made Geological Specimen)

Chert

Sedimentary cryptocrystalline quartz (SiO2)

Tumbled quartz

Quartz (silicon dioxide, SiO₂)

Beads (likely glass or man-made material)

N/A (artificial material)

Tumbled milky quartz

Quartz — silicon dioxide (SiO₂), cryptocrystalline or microcrystalline variety possible

Amber (likely raw amber)

Fossilized tree resin; organic mineraloid, commonly containing succinite (not a true mineral)

Tumbled purple quartz, possibly amethyst

Quartz (SiO₂), likely iron-colored amethyst or purple chalcedony

Obsidian

Volcanic Glass (Amorphous SiO2)

Carved greenstone figure

Likely nephrite jade (jadeite is a possible alternative), mainly amphibole-group minerals

Tumbled greenish stone, possibly serpentine or weathered quartzite

Tentative: serpentine-group minerals, chiefly Mg₃Si₂O₅(OH)₄; exact identification requires testing

Tumbled sodalite

Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂, likely with minor calcite or nepheline

Tumbled yellow jasper or chert

Microcrystalline quartz (SiO₂), likely iron-stained jasper/chert

Tumbled brown jasper

Microcrystalline quartz (SiO₂), commonly with iron-oxide inclusions

Pearl (Biogenic Mineral)

Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3

Unidentified weathered stone, likely quartz-rich metamorphic rock

Possibly quartzite or vein quartz; exact identification is uncertain from the image

Chert (flint), likely a knapped fragment

Microcrystalline quartz (SiO₂), also called cryptocrystalline quartz

Opalite

Synthetic Glass, SiO2 base with metallic inclusions

Small tumbled orange-brown mineral fragment

Indeterminate; possibly iron-stained quartz, carnelian, or orange calcite

Tumbled purple stone, possibly lepidolite-bearing rock or dyed quartzite

Uncertain from image; possible quartz (SiO₂) with purple mica, or artificially dyed silicate

Amber (Copal)

Succiniferous Resin

Tumbled milky quartz

Quartz (silicon dioxide, SiO₂)

Aura Quartz

Titanium-coated Silicon Dioxide (SiO2)

Chert

Sedimentary cryptocrystalline silica (SiO2)

Tumbled honey calcite (likely)

Calcite, calcium carbonate (CaCO₃)

Small rounded mineral pebble, possibly quartz

Uncertain; likely microcrystalline or crystalline SiO₂ (quartz), potentially with iron-oxide staining

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂), opaque-to-translucent milky variety

Flint

SiO2 (Cryptocrystalline Quartz)

Fossil coral fragment

Fossilized colonial coral, commonly *Hexagonaria* (often called Petoskey stone) or related scleractinian/tabulate coral

Malachite

Malachite, Cu₂CO₃(OH)₂; a banded botryoidal copper carbonate specimen

Chert (Flint)

Microcrystalline Quartz (SiO2)

Limonite (Iron Ore)

Hydrous Iron Oxide (goethite, lepidocrocite)

Polished fossiliferous chert or silicified limestone pebble

Microcrystalline quartz (SiO₂), possibly with calcite and iron-oxide inclusions

Blue Apatite

Fluorapatite / Chlorapatite [Ca5(PO4)3(F,Cl,OH)]

Polished vesicular basalt (likely scoriaceous basalt)

Basalt, aphanitic mafic volcanic rock; chiefly plagioclase, pyroxene, and iron-rich oxides

Quartz crystal fragment (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

Tumbled white stone, possibly quartz or marble

Uncertain; likely quartz (SiO₂) or calcite-rich marble (CaCO₃)

Flint (or Chert)

Cryptocrystalline Quartz (SiO2)

Polished/tumbled jasper, likely brecciated jasper

Jasper: microcrystalline quartz (SiO₂), with iron-oxide and other mineral impurities

Boulder Opal

Hydrated Silica (SiO2·nH2O)

Polished silver sheen obsidian heart

Obsidian (volcanic glass), primarily rhyolitic silica-rich glass

Glass Nugget (Tumbled Glass)

Amorphous Silicon Dioxide (SiO2) with additives

Smoky Quartz

Silicon Dioxide (SiO2)