Sedimentary Or Igneous Fragment

Quartz (Milky/Smoky Crystal fragment)

Silicon Dioxide (SiO2)

Weathered, quartz-rich metamorphic rock (likely schist or gneiss)

Quartz–feldspar–mica schist/gneiss, with surface lichens and iron-oxide staining

Fossilized Turtle Bone

Testudines fossil

Weathered basalt or iron-rich volcanic rock

Mafic volcanic rock, likely basalt; exact identification requires testing

Quartz Sand Grain / Micro Crystal

Silicon Dioxide (SiO2)

Gneiss (Gneissic Granite Pebble)

Metamorphic rock rich in Quartz, Feldspar, and Mica

Small quartz pebble or silica-rich mineral fragment

Quartz (SiO₂), tentative

Tumbled quartz-rich stone, possibly milky quartz or calcite

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

Milky quartz

Quartz (silicon dioxide, SiO₂)

Weathered metamorphic rock, possibly schist or gneiss

Indeterminate; likely quartz–feldspar–mica rock, potentially greenschist or gneiss

Quartz-rich rock fragment, possibly milky quartz or quartzite

Quartz (SiO₂), or quartzite if the grains are fused

Likely basalt fragment

Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine

Mica-bearing metamorphic rock, likely schist

Muscovite/biotite mica schist with quartz and feldspar

Gneiss (specifically Banded Gneiss)

Gneiss

Milky quartz vein fragment

Quartz (silicon dioxide, SiO₂), massive or granular variety

Pebble

Lithic fragment / Sedimentary clast

River Pebble

Weathered Sedimentary Rock Fragment

Waterworn Pebble / Quartzite

Metamorphic/Sedimentary rock fragment

Gneiss

Gneiss

Fossiliferous limestone / shell hash rock

Bioclastic limestone (calcarenite or coquina), dominantly CaCO₃

Granite (likely)

Granite, a coarse-grained felsic intrusive igneous rock composed mainly of quartz, feldspar, and mica

Likely quartz crystal fragment

Quartz (SiO₂), possibly a small tumbled or cleaved fragment

Clear quartz fragment

Quartz (silicon dioxide, SiO₂)

Conglomerate with Quartz Inclusions

Conglomerate (clastic sedimentary rock) with internal Quartz (SiO2)

Weathered fossil shell fragment

Likely a fossilized bivalve or gastropod fragment; exact taxon cannot be determined from one view

Weathered reddish-brown rock fragment

Probably altered basalt or fine-grained volcanic rock; exact identification requires testing

Mixed collection of quartz-rich rocks and minerals

Quartz (SiO₂), with some pieces possibly containing feldspar or mica; exact identification is uncertain from the image

Likely reddish granite/porphyritic igneous rock fragments

Feldspar–quartz–mica aggregate, possibly pink granite or rhyolite

Unidentified dark gray rock fragment

Likely fine-grained basalt or andesite; exact identification requires testing

Weathered fossiliferous limestone, likely coral or shell fragment

Calcite (CaCO₃), biogenic limestone; exact fossil taxon indeterminate from the image

Weathered basalt fragment

Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase and pyroxene, with possible olivine and iron-oxide alteration

Small brown rock fragment, likely sandstone

Quartz-rich sandstone (tentative identification)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Sedimentary or Igneous Matrix

Quartz

Silicon Dioxide (SiO2)

Quartz (Milk or Clear Variety)

Silicon Dioxide (SiO2)

Likely weathered schist or gneiss fragment

Micaceous quartz-feldspar metamorphic rock; exact identification requires testing

Dark basalt or fine-grained mafic rock

Basalt; primarily plagioclase feldspar, pyroxene, and commonly olivine or iron-titanium oxides

Quartz (Clear Quartz)

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Granite-like rock

Coarse-grained granitoid, likely granite or granodiorite

Quartz-veined metamorphic rock, likely schist or gneiss

Quartz–feldspar–mica rock; exact identification requires testing

Tumbled quartz crystal

Quartz (silicon dioxide, SiO₂)