Sedimentary Or Metamorphic Derived

Decorative polished pebbles

Likely mixed quartz-rich lithologies, including quartzite, jasper, and/or basalt

Blue Apatite

Apatite-(CaF), Ca5(PO4)3F

Limonite or Goethite (Ironstone)

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

Rounded river pebbles, likely quartz-rich sandstone or quartzite

Indeterminate quartz–feldspar rock; possible quartzite or arkosic sandstone

Pyrite (Cube variety)

Iron Sulfide (FeS2)

White quartz pebble (probable)

Quartz, silicon dioxide (SiO₂)

Marble

Metamorphosed Limestone (CaCO3)

Mica Schist

Mica Schist (predominantly Muscovite or Biotite sheet silicates)

Small red-brown mineral or rock fragment

Unidentified; possibly iron-oxide-rich jasper, garnet, or weathered sulfide

Jasper

Silicon Dioxide (SiO2) with impurities

Schist (Micaceous Schist)

Schist (containing mainly Muscovite and Quartz)

Marble

Recrystallized Calcite (CaCO3) or Dolomite (CaMg(CO3)2)

Copper-bearing Mica Schist

Mica Schist with Native Copper inclusions

Marble

Recrystallized Calcite (CaCO3) / Marble

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

White Agate / Chalcedony

Silicon Dioxide (SiO2)

Light-colored pebble, likely quartzite or weathered limestone

Indeterminate from image; possible quartzite (microcrystalline SiO₂)

Tiny rounded brown mineral grain

Indeterminate; possibly iron oxide, garnet, or a weathered sulfide grain

Hematite (Tumbled)

Iron(III) oxide (Fe2O3)

Small white mineral fragment

Likely quartz (SiO₂), possibly calcite (CaCO₃)

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Tumbled green aventurine (probable)

Quartz, SiO₂, with fuchsite or other green mica inclusions

Gneiss (specifically Granite Gneiss)

Gneiss (High-grade Regional Metamorphic Rock)

Banded gray stone, likely slate or fine-grained metamorphic rock

Probably slate or phyllite; composition commonly mica, quartz, and clay-derived minerals

Clear Quartz

Silicon Dioxide (SiO2) / Rock Crystal

Limonite (Iron Ore)

FeO(OH)·nH2O (Hydrous ferric oxide)

Pyrite in Matrix (likely Quartz or Coal)

Iron Sulfide (FeS2)

Pyrite-bearing rock (likely pyrite-rich ore)

Pyrite, FeS₂, in a fine-grained host rock

Small pale mineral fragment, likely quartz or calcite

Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing

Apatite

Fluorapatite (Ca5(PO4)3F)

Clear quartz crystals

Quartz (silicon dioxide, SiO₂)

Rounded quartz-rich pebble

Likely quartz arenite (quartz sandstone) or quartz-rich metamorphic pebble

Carnelian

SiO2 (Silicon Dioxide with Iron Oxide impurities)

Pink-and-black feldspar-rich metamorphic rock, likely gneiss

Biotite–feldspar gneiss, possibly pegmatitic granite-derived

Greenstone / River Siltstone

Metasedimentary Greenstone (Chlorite-rich Siltstone)

Fossilized bone fragment (probable mammalian tooth or bone)

Mineralized bone, commonly hydroxyapatite [Ca5(PO4)3(OH)] replaced or impregnated by silica/calcite

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Pyrite

Iron Sulfide (FeS2)

Slate or fine-grained shale

Slate; predominantly quartz, mica, and clay-derived minerals

Fluorite

Calcium Fluoride (CaF2)

Pyrite

Iron Sulfide (FeS2)