Sedimentary Rock (Possibly Composed Of Various Minerals)

Tumbled dark stone, possibly basalt

Basalt; fine-grained mafic rock composed mainly of plagioclase and pyroxene, with possible olivine

Sandstone

Arenite (typically composed of SiO2)

Hag Stone

Perforated Sedimentary Rock (typically Flint, Chert, or Limestone)

Quartz with Inclusions

Silicon Dioxide (SiO2)

Sandstone

Arenite (SiO2 based)

Sandstone

Arenite (primarily SiO2)

Vesicular basalt (possibly scoria)

Basalt; chiefly plagioclase feldspar, pyroxene, and often olivine, with volcanic glass

Sandstone

Sandstone (Quartzose/Feldspathic Sandstone)

Dark gray slate (possibly argillite or shale)

Slate, a low-grade metamorphic rock derived mainly from shale; composition commonly quartz, illite/muscovite, chlorite, and clay minerals

Sandstone Pebble

Sedimentary Rock (Quartz Arenite)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Gneiss

Gneiss

Sandstone

Arenite (composed primarily of SiO2)

Sandstone

Arenite (primarily SiO2 - Silicon Dioxide)

Tumbled pale greenish stone, likely serpentine or altered limestone

Probable serpentine-group rock (antigorite/lizardite), possibly serpentinite; identification is visual only

Quartz-bearing altered rock, possibly iron-stained quartz vein

Quartz (SiO₂) in a feldspathic/sericitized host, with iron-oxide staining

Quartz Arenite / Sandstone

Quartz sandstone (SiO2 rich clastic sedimentary rock)

Vesicular quartz-rich rock, possibly weathered rhyolite or hydrothermal quartz

Likely quartz (SiO₂) with altered feldspar, iron oxides, and cavities; exact identification requires testing

Likely weathered quartz-rich stone or fossil fragment

Indeterminate; possibly quartz-bearing sandstone, iron-stained quartz, or a fragmentary fossil

Fossilized Horn Coral

Rugosa

Sandstone

Arenite (composed primarily of SiO2)

Gastropod Steinkern (Internal Mold Fossil)

Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix

Sandstone

Arenite (composed primarily of SiO2)

Lapis Lazuli (polished cabochon)

Lazurite-rich metamorphic rock (approx. Na6Ca2Al6Si6O24(SO4,S,Cl)2)

Lapis Lazuli

Sodium aluminum silicate with sulfur (main component: Lazurite [(Na,Ca)8(AlSiO4)6(SO4,S,Cl)2])

Sandstone

Sedimentary Clastic Rock

Unakite

Epidotized Granite

Biotite Granite

Phaneritic Felsic Igneous Rock

Blue glass-like tumbled specimen

Most likely cobalt-blue slag glass or manufactured glass; not confidently identifiable as a natural mineral from the image

Sandstone

Arenite (primarily SiO2)

Quartz

Quartz (SiO₂)

Gneiss (High-Grade Metamorphic Rock)

Gneiss (primarily composed of Quartz, Feldspar, and Mica/Amphiboles)

River Pebble (Likely Chert or Fine-Grained Sandstone/Quartzite)

Siliciclastic clast (likely Chert or Quartzarenite/Quartzite pebble)

Sandstone

Sedimentary Rock (Quartz Sandstone)

Weathered brown stone, likely basalt or iron-stained volcanic rock

Indeterminate; possibly vesicular basalt (mafic silicate rock)

Magnetite

Fe3O4 (Iron(II,III) oxide)

Sandstone (River Rock)

Arenite (composed primarily of SiO2)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Sandstone

Sandstone (composed predominantly of SiO2)

Sandstone

Arenite

Chakra Stone (Composite / Man-made Bonded Gemstones)

Composite of Quartz, Lapis Lazuli, Aventurine, Tiger's Eye, and Jasper (SiO2, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, etc.)

Sandstone

Arenite (composed mainly of SiO2)