Organic (Paper And Cellulose)

Banded Gneiss River Pebble

Gneiss

Polished pale stone, likely limestone or quartzite pebble

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

Orthoceras Fossil Limestone

Orthoceras (extinct genus of cephalopod); Limestone matrix (CaCO3)

Polished banded agate pebble

Chalcedony (microcrystalline quartz), SiO₂, with iron-oxide or other mineral banding

Chalcedony Nodule (Carnelian/Agate)

Chalcedony (Silicon Dioxide, SiO2)

Magnetite-rich black sand

Magnetite (Fe₃O₄), likely mixed with other heavy minerals

Polished yellow-brown stone, likely serpentine or jasper

Serpentine-group mineral aggregate, commonly antigorite/lizardite; possibly iron-rich jasper

Tumbled black stone, likely basalt or black jasper

Probably basalt (fine-grained plagioclase–pyroxene rock); exact identification is uncertain from the image

Limestone

Calcareous sedimentary rock (CaCO3)

Limestone

Calcium Carbonate (CaCO3)

Red Jasper

Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)

Polished agate (likely moss or plume agate)

Microcrystalline quartz, SiO₂, chiefly chalcedony with possible included iron oxides

Fossil coral fragment

Likely fossilized colonial coral, commonly Hexagonaria (Petoskey stone) or related tabulate coral

Quartz-lined agate/geode slice

Microcrystalline quartz (chalcedony, SiO₂) with drusy quartz; possibly calcite inclusions

Milky quartz (likely tumbled or polished)

Quartz, silicon dioxide (SiO₂)

Thunderegg (Agetized Geode nodule)

Rhyolitic Agate Nodule (SiO2 filling volcanic cavities)

Granite with Orthoclase and Hematite Staining

Phaneritic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)

Optical Calcite (Iceland Spar)

Calcite (Calcium Carbonate, CaCO3)

Granite (with Quartz Vein and Biotite)

Granite (Plutonic Igneous Rock)

Pyrite

Iron Sulfide (FeS2)

Orange chalcedony (carnelian), possibly amber

Carnelian: microcrystalline quartz, SiO₂; amber: fossilized plant resin

Polished black stone, possibly black marble or basalt

Probable fine-grained mafic rock; exact identification requires testing

Polished basalt sphere

Basalt; predominantly plagioclase feldspar, pyroxene, and commonly olivine

Banded Agate

Cryptocrystalline Quartz (SiO2)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Likely anthracite coal

Anthracite; predominantly carbon (C), with minor mineral impurities

Petrified wood

Silicified wood, commonly quartz/chalcedony (SiO₂) replacing woody tissue

Polished black agate geode slice

Microcrystalline quartz (chalcedony), SiO₂, with possible iron-oxide matrix and druzy quartz

Polished brown pebble, likely jasper or iron-stained quartzite

Uncertain; possible microcrystalline quartz (SiO₂) with iron-oxide staining

Quartz Pebble with Muscovite Mica

Quartzite / Quartz-Mica Schist pebble (SiO2 with KAl2(AlSi3O10)(OH)2)

Polished banded stone, likely black marble or banded gneiss

Graphitic banded marble or quartz-feldspar biotite gneiss; exact identification requires testing

Tumbled amber-colored agate or jasper

Microcrystalline quartz (SiO₂), likely chalcedony with iron-oxide inclusions

Tumbled white quartzite or milky quartz

Quartzite; predominantly microcrystalline quartz (SiO₂), though a quartz pebble is also possible

Tumbled greenstone / altered basalt pebble

Fine-grained mafic volcanic rock, likely basalt or greenstone; commonly composed of plagioclase, pyroxene, chlorite, epidote, and iron oxides

Dyed and polished agate heart

Microcrystalline quartz (chalcedony), SiO₂; likely druzy quartz inclusions

Kaolinite Claystone

Al2Si2O5(OH)4 (Kaolinite)

Rounded quartz-rich sandstone pebble

Quartz arenite or feldspathic sandstone; primarily SiO₂ quartz grains with minor feldspar, iron oxides, and clay minerals

Polished mixed rock, likely orbicular/epidote-bearing granite or basalt

Uncertain; probable quartz–feldspar–amphibole/epidote aggregate

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Limestone or Chalk

Calcium Carbonate (CaCO3)

Polished fossil coral

Fossilized colonial coral, commonly tabulate or rugose coral; calcite (CaCO₃) replacement

Tumbled brown-and-white feldspar-rich stone, likely granite or quartzite

Indeterminate; probably quartz–feldspar aggregate (granite) or quartzite, with iron-oxide staining