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Shale or Mudstone (Based on appearance)

Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)

Smoky Quartz

SiO2 (Silicon Dioxide)

Iron Meteorite

Iron-nickel alloy (primarily kamacite and taenite)

Pumice

Pumicite (Amorphous glass with varying chemical composition, often rhyolitic)

Scoria (Vesicular Basalt)

Vesicular Basalt

Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)

Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.

Sandstone

Sandstone (Clastic Sedimentary Rock)

Calcite

Calcite (Mineral, Calcium Carbonate - CaCO3)

Quartz (likely milky/rose quartz variety)

Quartz (SiO2 - Silicon Dioxide)

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2

Labradorite (a variety of Feldspar)

Labradorite; (Na,Ca)(Al,Si)4O8 (a plagioclase feldspar)

Granite

Granite (Mainly Quartz, Feldspar, and Mica/Amphibole)

Chert (variant of Flint)

Chert (SiO2)

Quartz

Silicon Dioxide (SiO2)

Halite

Halite (NaCl)

Carnelian Agate

Red Chalcedony (SiO2 with Iron Oxide impurities)

Quartzite Pebble

Quartzite (mostly SiO2)

Halite (Rock Salt)

Halite; NaCl (Sodium Chloride)

Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)

Chert (microcrystalline quartz)

Marble

Marble (metamorphosed limestone/dolostone). Predominantly composed of Calcite (CaCO3) for marble derived from limestone, or Dolomite (CaMg(CO3)2) for marble derived from dolostone.

Pyrite

Pyrite (FeS2)

Pumice

Pumice (volcanic rock)

Citrine Quartz

Citrine (Silicon Dioxide - SiO2)

Amethyst Geode/Cluster

Quartz (SiO2) - variety Amethyst

Diamond

Diamond (pure carbon; C)

Chert (varieties include Flint or Jasper)

Chert (cryptocrystalline quartz; SiO₂)

Chert (or Flint)

Chert (a cryptocrystalline variety of quartz, SiO2)

Larimar

Pectolite (a blue variety of Pectolite)

Petoskey Stone

Hexagonaria percarinata (Fossilized Rugose Coral)

Porphyritic Basalt or Diabase with Plagioclase Phenocrysts

Porphyritic Basalt or Diabase; Mineral: Plagioclase Feldspar

Schist

Schist (various mineral compositions)

Slate

Slate (a fine-grained, foliated metamorphic rock). Mineral composition: Primarily composed of mica minerals (muscovite, chlorite, sericite) and quartz, with minor amounts of hematite, pyrite, and other accessory minerals.

Chert / Flint (a variety of Chert)

Chert (SiO2)

Ruby

Corundum (Al₂O₃) with Chromium (Cr)

Quartz (Iron-stained)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Blue Chalcedony and Picture Jasper Beads

Blue Chalcedony (SiO2), Picture Jasper (SiO2)

Marble

Recrystallized Calcite / Dolomite (CaCO3)

Onyx Marble (also commonly called Onyx)

Calcite (CaCO3), often with other mineral impurities

Aura Quartz Geodes (Lab-Altered)

Silicon Dioxide (SiO2) with Metallic Vapor Deposition

Granite Pebble

Granite (composition of Quartz, Alkali Feldspar, and Plagioclase)

Sunstone

Plagioclase Feldspar (containing (Ca,Na)(Al,Si)4O8 with Hematite or Copper inclusions)

Sunstone

Plagioclase Feldspar (Na,Ca)(Al,Si)4O8