Mineralogical

Sugilite

Sugilite (KNa2(Fe,Mn,Al)2Li3Si12O30)

Porphyritic Rhyolite or Andesite (Porphyry)

Porphyritic igneous rock (Composition depends on exact mineralogy, often Rhyolite or Andesite)

Pegmatite (likely Granitic Pegmatite)

Pegmatite (a coarse-grained igneous rock, often with granitic composition)

Likely small metallic meteorite fragments

Unclassified iron or stony-iron meteorite; mineralogy cannot be confirmed from the image

Polished pale stone, likely limestone or quartzite pebble

Most consistent with micritic limestone (calcite, CaCO₃), though the image cannot confirm mineralogy

Sandstone

Quartz Arenite (a common type of sandstone, given the appearance), Arkose, Greywacke (depending on mineralogy)

Cubic Zirconia

Zirconium dioxide (ZrO2)

Hypersthene (or Enstatite/Ferrosilite)

Orthopyroxene series (Mg,Fe)SiO3 - specifically, historically hypersthene (intermediate member) now referred to as Enstatite (Mg-rich) or Ferrosilite (Fe-rich)

Granite (likely a river or beach pebble)

Granite (a felsic intrusive igneous rock primarily composed of quartz, feldspar, and mica)

Greisen

Greisen

Tektite (Indochinite)

Tektite (High-silica natural glass)

Banded Gneiss

Gneiss (pronounced 'nice')

Pebble (likely a type of sandstone or quartzite pebble)

Clastic Sediment (specifically, a rudite-sized clast). If the pebble is composed of a specific rock type, its scientific name would be that rock type (e.g., 'Quartzite pebble', 'Granite pebble', 'Chert pebble'). Given its appearance, it is likely a metamorphic quartzite pebble or a hard sandstone pebble.

Dark Igneous Rock (Likely Basalt or Diabase)

Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.

Jade

Jadeite or Nephrite

Amber

Succinite (Organic Mineraloid)

Pearl (Biogenic Mineraloid)

Calcium carbonate (CaCO3) primarily as Aragonite

Pearl (Biogenic Mineraloid)

Calcium carbonate (Aragonite) and Conchiolin, CaCO3

Black Pearl (Tahitian Pearl)

Aragonite / Calcite (CaCO3) with Conchiolin

Abalone Shell (Nacre)

Aragonite (CaCO3) - Biogenic Mineral

Anthracite Coal

Anthracite (Carbon-rich mineraloid)

Amber

Succinite (Organic Mineraloid) - C10H16O

Pearl

Aragonite / Calcium Carbonate (CaCO3)

Pearl

Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3

Pearl

Organic Mineraloid (CaCO3 + Conchiolin)

Pearl

Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3

Green Opal

Hydrated Silica (SiO2·nH2O)

Amber

Succinite (organic mineraloid); Chemical formula: C10H16O

Pearl (Biogenic Mineral)

Calcium Carbonate (primarily Aragonite) with Conchiolin; CaCO3

Shungite

Shungite (carbon-rich Precambrian mineraloid)

Precious Opal

Hydrated Silica (SiO2·nH2O)

Limonite/Ironstone

Limonite (FeO(OH)·nH2O)

Shungite

Carbon-rich mineraloid (Amorphous carbon)

Opal (in Jewelry Setting)

Hydrated Silicon Dioxide (SiO2·nH2O)

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Opalite

Man-made Glass (Synthetic Opalized Glass)

Fire Opal (in Matrix)

Hydrated Silica (SiO2·nH2O)

Obsidian

Obsidian

Black Opal Ring (Carved Opal)

Hydrated Silicon Dioxide (SiO2·nH2O)

Opal (Precious Opal)

Hydrated Silica (SiO2·nH2O)

Precious Opal

SiO2·nH2O (Hydrated Silicon Dioxide)

Amber with Inclusion

Succiniferous fossil resin (C10H16O)