Sedimentary Rock (Possibly Composed Of Various Minerals)

Marble

Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).

Celestine (Celestite)

Strontium Sulfate (SrSO4)

Chert (Jasper or Flint variant)

Chert (composed of microcrystalline quartz, SiO2)

Fossilized Sand Dollar

Echinoidea (Clypeasteroida)

Garnet in Schist (Garnetiferous Micaceous Schist)

Almandine Garnet, Fe3Al2(SiO4)3

Shale (possibly Carbonaceous or Oil Shale)

Laminated Mudstone (primarily clay minerals and quartz)

Rough Diamond

Carbon (C)

Sandstone (specifically Lithic or Quartz Arenite)

Arenite (composed primarily of SiO2)

Limonite with Hematite

Hydrated iron(III) oxide-hydroxide with variable composition (FeO(OH)·nH2O)

Red Sandstone

Arenite (with Iron Oxide / Hematite cementation)

Unakite

Altered Granite (Epidotized Granite)

Chert (Flint)

Chert (SiO2)

Fossil Snail Shell (Embedded in Resin)

Gastropoda fossil

Iron-stained weathered stone (tentative)

Undetermined; possibly weathered iron-rich basalt or concretion

Bauxite

Aluminum ore (mixture of gibbsite Al(OH)3, boehmite γ-AlO(OH), and diaspore α-AlO(OH))

Sandstone with Manganese Oxide Patina

Clastic Sedimentary Rock (primarily SiO2)

Pink Granite

Phaneritic Felsic Igneous Rock

Polished orbicular jasper

Orbicular jasper; microcrystalline quartz (SiO₂) with hematite/goethite and other silicate inclusions

Dark coarse-grained rock, likely basalt or gabbro

Basalt (fine-grained) or gabbro (coarse-grained), composed mainly of plagioclase feldspar and pyroxene

Sandstone

Clastic Sedimentary Rock

Sandstone

Arenite (composed primarily of SiO2)

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.

Concrete

Anthropogenic Sedimentary Rock (Hydrated Calcium Silicate)

Slate

Slate (foliated metamorphic rock)

Sandstone (Quartz Sandstone / Iron-stained Sandstone)

Sandstone (SiO2 with iron oxide impurities)

Gneiss

Gneiss (Foliated Metamorphic Rock)

Conglomerate

Conglomerate (Clastic sedimentary rock)

Fossil Shell

Invertebrate fossil (Mollusca)

Sandstone

Arenite (Clastic Sedimentary Rock)

Garnet-bearing Schist / Conglomerate Specimen

Metamorphic rock with almandine garnet porphyroblasts

Granite Pebble

Phaneritic intrusive igneous rock

Granite

Phaneritic Felsic Igneous Rock

Sandstone (Ferruginous)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 cement)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3 staining)

Quartz

Quartz (SiO₂ - Silicon Dioxide)

Weathered brown stone, possibly basalt or iron-rich sedimentary rock

Indeterminate from photograph; likely fine-grained mafic rock (basalt) or ferruginous sandstone

Brecciated stone pebble

Breccia

Likely weathered brown quartz-bearing rock

Tentatively weathered granite or granitic gneiss; exact identification is uncertain from the photograph

Unknown Organic Object (likely a berry or fruit)

Not applicable; this is not a geological specimen. If it were a cranberry, its scientific name would be Vaccinium macrocarpon; if a cherry, it would be Prunus avium or Prunus cerasus.

Limonite Geode (Ironstone Concretion)

FeO(OH)·nH2O (Hydrated Iron Oxide)

Unidentified dark reddish-brown rock or mineral specimen

Indeterminate from the blurred image; possibly iron-stained quartz, jasper, or a metallic sulfide-bearing rock

Fossil coral fragment

Likely calcitic colonial coral, possibly fossilized scleractinian coral