Metamorphic (Likely Gneiss Or Schist Based On Texture)

Aura Quartz Bead

Silicon dioxide (SiO2) with metal coating

Light Green Quartzite

Metamorphosed Quartz Sandstone (SiO2 with chlorite or mica inclusions)

Quartz with impurities or Host Rock

SiO2 (Silicon Dioxide) with mixed silicates

Polished Marble (likely Carrara-type with Iron oxides)

Metamorphosed Carbonate (CaCO3)

Quartz (River Cobble)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Rounded greenstone pebble

Likely serpentinite or chlorite-rich metamorphic rock; exact identification requires testing

Weathered brown stone, likely sandstone or iron-stained granite

Indeterminate; possible quartz-rich sandstone (quartz, feldspar, iron oxides)

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

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

Dumortierite Quartz

Al7(BO3)(SiO4)3O3

Dark metamorphic rock, likely hornfels or fine-grained basalt

Probable hornfels; commonly quartz–feldspar–mica with variable amphibole/pyroxene

Porphyritic Andesite

Andesite

Granite

Granite (Phaneritic Acidic Igneous Rock)

Limestone (likely weathered)

Limestone (Mainly Calcium Carbonate, CaCO3)

Weathered quartz-rich rock, possibly sandstone or quartzite

Indeterminate; likely quartz sandstone (SiO₂-rich), possibly weakly metamorphosed quartzite

Quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly quartz (SiO₂), with minor iron-oxide and mica impurities

Dark green metamorphic rock, likely serpentinite

Serpentinite, composed mainly of serpentine-group minerals (antigorite, lizardite, or chrysotile), commonly with magnetite and minor chlorite/talc

River Pebble (Granite/Gneiss)

Granitic Pebble / Quartz-Feldspar Aggregate

Granite / Gneiss Ballast Rock

Granite (Quartzo-feldspathic rock)

Mixed Gemstone Bracelet

Mixed natural minerals and rocks (e.g., Rhodonite, Malachite, Sodalite, Rose Quartz, Black Tourmaline, Quartz/Chalcedony variants)

Chert (Quartz)

Silicon dioxide (SiO2)

Quartzite Pebble

Quartzite (primarily SiO2)

Shungite

Non-crystalline carbon (similar to anthracite coal or meta-anthracite)

Banded Chert

Silicon Dioxide (SiO2)

Glaucophane / Blueschist

Glaucophane (Na2Mg3Al2Si8O22(OH)2)

Granite Pebble

Granite

Ferruginous Siltstone or Mudstone

Ferruginous Siltstone / Goethitic Sandstone

Chert / Jasper

Silicon Dioxide (SiO2)

Quartz (Small Fragment)

Silicon Dioxide (SiO2)

Shale

Clastic sedimentary rock (primarily clay and silt minerals)

River Cobble (Quartzite)

Quartzite (SiO2)

Basalt

Mafic Igneous Pebble

Quartz with Mica inclusions (Pegmatite)

Silicon Dioxide (SiO2) with Muscovite/Biotite inclusions

Amazonite

Microcline (KAlSi3O8) with Trace Elements

Pale granite pebble (tentative identification)

Granite; a coarse-grained felsic intrusive igneous rock composed primarily of quartz and feldspar, with minor mica or amphibole

Jade (likely Nephrite or Jadeite)

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)

Green Aventurine

Aventurine Quartz (SiO2 with Fuchsite inclusions)

Bornite

Bornite (Cu5FeS4)

Mixed collection of natural stones

Several unidentified lithologies, likely including basalt, granite, quartzite, sandstone, and weathered metamorphic rocks

Rounded quartz-rich beach pebble

Likely milky quartz or quartzite (SiO₂)

Likely dark rounded pebbles

Indeterminate; possibly basalt or a dark mafic mineral such as hornblende/biotite