Man Made Metamorphic Style Composite

Dark quartz point (possibly smoky quartz)

Quartz, SiO₂; the dark color may indicate smoky quartz, but the image is insufficient to confirm

Schist

Schist

Red Sandstone

Arenite (Ferruginous Sandstone)

Clear calcite cleavage fragment

Calcite (calcium carbonate, CaCO₃)

Sandstone (Pebble)

Sandstone (arenite, arkose, wacke depending on composition)

Likely weathered gneiss or mica-rich schist

Foliated metamorphic rock, probably quartz–feldspar–biotite gneiss/schist

Rounded quartz-rich cobble, likely quartzite

Quartzite; predominantly SiO₂ (recrystallized quartz)

Likely slate fragment

Slate; predominantly fine-grained mica/clay minerals and quartz

Banded malachite cabochon

Malachite, Cu₂CO₃(OH)₂; the dark bands may be manganese-oxide or other sulfide-rich matrix, and could also indicate a composite or treated specimen

Talc

Talc (Mg₃Si₄O₁₀(OH)₂)

Milky Quartz

Silicon Dioxide (SiO2)

Weathered quartz-rich rock, possibly quartzite

Quartzite; predominantly microcrystalline quartz (SiO₂)

Quartzite Pebble

Metamorphic rock predominantly composed of Quartz (SiO2)

Pebble (likely Quartz or Chert)

SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.

Likely quartz fragment

Quartz (silicon dioxide, SiO₂)

Quartzite Pebble

Metamorphic rock predominantly composed of Quartz (SiO2)

Quartz (likely Milky Quartz)

Quartz (SiO₂ - Silicon Dioxide)

Obsidian (Black)

Obsidian (High-silica volcanic glass)

Quartz fragment

Quartz, silicon dioxide (SiO₂)

Biotite (Black Mica)

K(Mg,Fe)3AlSi3O10(OH,F)2

Quartz (pebble)

Quartz (SiO₂)

Fossil crinoid columnal in limestone

Crinoidea indet.; calcitic ossicle (CaCO₃)

Quartzite

Metamorphic rock primarily composed of Quartz (SiO2)

Quartzite Pebble

Metamorphic rock predominantly composed of Quartz (SiO2)

Quartzite

Quartzite (Metamorphic rock primarily composed of SiO2)

Quartzite

Metamorphic rock predominantly composed of Quartz (SiO2)

Quartzite

Metamorphic rock predominantly composed of Quartz (SiO2)

Garnet

Almandine (Fe3Al2(SiO4)3)

Diabase (Greenstone)

Diabase (Dolerite)

Tumbled quartz-rich stone, possibly quartzite

Quartzite (mostly SiO₂), possibly pale jasper or chalcedony

Milky quartz

Quartz, silicon dioxide (SiO₂)

Amphibolite

Hornblende amphibolite; chiefly hornblende and plagioclase feldspar

Petrified wood

Silicified wood; commonly quartz/chalcedony (SiO₂) replacing organic tissue

Likely polished leopard-skin jasper or brecciated jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), with iron-oxide and other mineral inclusions; exact variety cannot be confirmed from the image alone

Engineered Quartz

Silicon dioxide composite

Milky Quartz

Silicon Dioxide (SiO2)

Milky quartz

Quartz (silicon dioxide, SiO₂)

Zebra marble

Banded calcite marble, commonly called zebra marble; chiefly calcite (CaCO₃), sometimes with dolomite and dark silicate or carbonaceous minerals

Quartzite

Metamorphic rock primarily composed of Quartz (SiO2)

Unakite

Epidotized Granite

Weathered iron-rich metamorphic rock, likely banded ironstone or quartzite

Ferruginous quartzite/itabirite; mainly quartz (SiO₂) with iron oxides such as hematite and goethite

Tumbled white stone beads, likely marble or quartz

Undetermined; possibly marble (recrystallized calcite, CaCO₃) or milky quartz (SiO₂)