Man Made Material (Jewelry, Metal Alloy)

Milky Quartz

Silicon Dioxide (SiO2)

Peridot (Olivine)

Olivine, (Mg, Fe)2SiO4

Milky Quartz

Quartz / Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz (Common or Milky)

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Diamond

C (Carbon)

Amethyst (likely rough or cleaved fragment)

Quartz, silicon dioxide (SiO₂), purple variety colored mainly by iron impurities and irradiation

Green Jasper

Quartz (Silicon Dioxide, SiO2) with iron silicate inclusions

Jasper

Silicon Dioxide (SiO2), Microcrystalline Quartz

Petrified Wood

Silicified Wood (SiO2 permineralization)

Fossil Shark Tooth

Carcharodon or Carcharias fossil (Vertebrate Fossil)

Serpentinite

Serpentinite (a rock composed predominantly of serpentine group minerals)

Ocean Jasper

Orbicular Jasper, Chalcedony (SiO2)

Amethyst cluster

Quartz, silicon dioxide (SiO₂), purple variety colored mainly by iron impurities and irradiation

Chert (variations include Flint/Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Zebra Marble

Metamorphosed Limestone (Recrystallized Calcite)

Fossilized Shark Tooth

Chondrichthyes (Class)

Fossilized Shark Tooth

Chondrichthyes (Class)

Polished Red Quartz (or Carnelian / Red Jasper)

Silicon Dioxide (SiO2)

Green tourmaline (likely elbaite)

Tourmaline group; likely elbaite, complex borosilicate such as Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Calcite-rich limestone fragment

Limestone, predominantly calcite (CaCO₃), possibly micritic or fossiliferous

Feldspar-rich igneous rock, likely granite or gneiss fragment

Granite-like quartz–feldspar rock; exact identification is uncertain from the blurred image

Vesicular basalt (scoriaceous basalt)

Basalt, primarily plagioclase, pyroxene, and iron-rich olivine; vesicular variety may be termed scoria

Rounded river or beach pebble

Likely quartz-rich sandstone or quartzite; exact identification requires a close-grained view and hardness test

Tumbled white chalcedony (milky agate)

Microcrystalline quartz, SiO₂; chalcedony, locally grading toward milky agate

Tumbled carnelian

Carnelian, a red-orange variety of chalcedony (microcrystalline quartz, SiO₂)

Likely weathered quartz-bearing rock fragment

Indeterminate; appears to contain quartz (SiO₂) with iron-oxide staining, possibly from quartzite, granite, or pegmatite

Dark vesicular volcanic rock, likely basaltic scoria

Scoria (vesicular basalt; composition commonly plagioclase, pyroxene, and iron-rich glass)

Druzy quartz geode

Microcrystalline quartz (SiO₂), commonly lining a volcanic geode cavity

Weathered pink granite fragment

Granite, chiefly quartz, potassium feldspar, and plagioclase feldspar with minor mica

Amethyst geode slices

Amethyst, purple quartz (SiO₂)

Unidentified weathered rock, possibly quartz-bearing granite or rhyolite

Indeterminate; likely quartz–feldspar-rich silicate rock

Tumbled quartzite pebble

Quartzite, predominantly crystalline SiO₂

Weathered granite or granitic gneiss pebble

Granite; mainly quartz (SiO₂), feldspar, and mica, with possible gneissic alteration

Leopard Skin Jasper

Silicon Dioxide (SiO2) with mineral inclusions

Smoky Quartz

Silicon Dioxide (SiO2)

Amber

Succinite (organic gemstone, approx. C10H16O)

Siltstone Pebble

Siltstone (composed of siliciclastic grains)

Porphyritic Rhyolite (Llanite or similar)

Porphyritic Rhyolite / Quartz-Feldspar Porphyry