This Appears To Be A Man Made Metallic Object, Likely Jewelry, Not A Natural Rock, Mineral, Or Geological Specimen.

Diamond

Carbon (C)

Tiger's Eye

Tiger's Eye (a variety of Chalcedony, which is a microcrystalline quartz with fibrous inclusions of oxidized crocidolite)

Clear Quartz

SiO2 (Silicon Dioxide)

Fluorite in Matrix

Fluorite (CaF2) within a host rock matrix

Quartz Pebble (Chalcedony/Agate variety)

Silicon Dioxide (SiO2)

Chalcedony (or a variety of Chalcedony, likely Agate or Jasper)

Chalcedony (SiO₂)

Diamond (Set in jewelry)

Cubic Carbon (C)

Quartz (likely milky/gray variety)

Quartz (SiO₂)

Quartz Crystal

Quartz (SiO₂)

Quartz (specifically Milky/Gray Quartz vein)

Silicon Dioxide (SiO2)

Peacock Ore

Bornite (Cu5FeS4)

Quartz with Inclusions

Silicon Dioxide (SiO2) with various mineral inclusions

Blue Agate (Tumbled and Dyed)

Silicon Dioxide (SiO2) with likely organic dyes

Calcite (likely a tumbled specimen)

Calcite (CaCO 3 )

Blue Chalcedony (likely dyed Agate)

Silicon Dioxide (SiO₂)

Quartz / Common Agate

Silicon Dioxide (SiO2)

Granitoid (Granite/Granodiorite)

Plutonic igneous rock (variable composition, primarily SiO2)

Pyrite

Iron Disulfide (FeS2)

Hematite

Iron(III) oxide (Fe2O3)

Dyed Howlite (simulating Lavender/Purple Jade or Charoite)

Howlite: Ca2B5SiO9(OH)5 (when natural)

Grass (Organic Matter/Soil)

Poaceae (family of monocotyledonous flowering plants)

Quartz Geode

Silicon Dioxide (SiO2) within a geode

Granite

Plutonic Igneous Rock (composed typically of SiO2, Al2O3, K2O, Na2O, CaO)

Bituminous Coal (with Anthracite or Vitrinite inclusion)

Organic-rich Sedimentary Rock (Carboniferous classification)

Amethyst Geode

Silicon Dioxide with trace inclusions of Iron (SiO2)

Sandstone

Arenite (primarily SiO2 - Silicon Dioxide)

Sandstone

Clastic sedimentary rock (Quartz arenite/Arkose)

Chalcedony (Agate/Jasper mix in host rock)

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

Smoky Quartz

Smoky Quartz (SiO2)

Granite (Alkali-feldspar rich)

Phaneritic Felsic Igneous Rock (Major components: KAlSi3O8, SiO2)

Quartz (likely Yellow/Orange variety, possibly Citrine or Chalcedony with iron staining)

Quartz (SiO₂)

Iron Slag

Anthropogenic Vitreous Silicate (Byproduct of Smelting)

Quartz (likely Rose Quartz or Milky Quartz based on color)

Quartz (SiO2 - Silicon Dioxide)

Quartz (Orangey-white variety)

Silicon Dioxide (SiO2)

Green Aventurine

Quartz (SiO2) with Fuchsite inclusions

Quartz (Flesh-colored or Rose Quartz variety)

Silicon Dioxide (SiO2)

Gold Nugget

Native Gold (Au)

Limonite (with goethite)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Herkimer Diamond

Quartz (SiO2)

Chalcedony (Agate Pebble)

Silicon Dioxide (SiO2)

Lapis Lazuli

A metamorphic rock primarily composed of lazurite (Na,Ca)8[(S,SO4,Cl)2|(Al6Si6O24)], calcite (CaCO3), and pyrite (FeS2).

Geode with Quartz and possibly Jasper/Hematite

Quartz (SiO2) and Chalcedony (cryptocrystalline SiO2), possibly stained by iron oxides