Metamorphic (Altered Igneous Rock)

Green-and-white quartz-rich rock, likely chrysoprase or serpentine-bearing stone

Uncertain; possible chrysoprase (microcrystalline quartz, SiO₂) or serpentinite (magnesium silicate minerals)

Quartz

Silicon Dioxide (SiO2)

Turquoise

Turquoise (Hydrated phosphate of copper and aluminium), CuAl6(PO4)4(OH)8·4H2O

Weathered schist or gneiss fragment

Quartz–feldspar–mica metamorphic rock; likely mica schist or gneiss

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Weathered quartz-rich rock, likely quartzite or altered sandstone

Quartzite (mostly microcrystalline quartz, SiO₂); exact identification is uncertain from the photograph

Banded Gneiss

Gneiss (Metamorphic Rock)

Likely weathered sandstone fragment

Quartz-rich sandstone, predominantly SiO₂ with minor feldspar and iron-oxide cement

Gneiss

High-grade metamorphic rock (Gneiss)

Auriferous Quartz (Gold-bearing Quartz)

Silicon Dioxide (SiO2) with trace Gold (Au) and Iron Oxides

Tumbled yellow jasper (likely serpentine or calcite-rich stone)

Jasper: microcrystalline quartz (SiO₂); exact yellow veining may indicate serpentine, calcite, or iron oxides

Weathered feldspar-rich pegmatite (likely orthoclase or plagioclase)

Granitic pegmatite; predominantly K-feldspar/plagioclase (KAlSi₃O₈–NaAlSi₃O₈), with quartz and dark mafic minerals

Unakite

Unakite (Altered Granite consisting of Orthoclase KAlSi3O8, Epidote Ca2(Al,Fe)3(SiO4)3(OH), and Quartz SiO2)

Gneiss

Gneiss (High-grade metamorphic rock)

Quartz (Iron-Stained)

Silicon Dioxide (SiO2)

Biotite Mica

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

Weathered sandstone (probable)

Quartz-rich sandstone, largely composed of cemented quartz grains (SiO₂)

Weathered limestone or calcitic fossil/reef fragment

Calcite-rich limestone (CaCO₃), possibly fossiliferous limestone

Quartz

Silicon Dioxide (SiO2)

Unidentifiable Rock Fragment

Serpentinite (probable)

Serpentinite, dominated by serpentine-group minerals (chrysotile, lizardite, or antigorite), commonly with magnetite

Banded Gneiss

Gneiss (Metamorphic rock)

Granite / Gneiss (Felsic Metamorphic or Igneous Rock)

Gneiss (or weathered Granite)

Milky Quartz

Silicon Dioxide (SiO2)

Basalt Pebble

Extrusive Igneous Rock

Unakite-veined Granite / Epidotized Granite

Epidotized Granite (FeCu2Al2(Si2O7)(SiO4)(OH)2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Purpurite

Manganese Iron Phosphate, Mn3+(PO4)

Quartz Crystal Rock

Silicon Dioxide (SiO2)

Unakite

Altered Granite (composed of pink orthoclase feldspar, green epidote, and quartz)

Rounded greenish river pebble, likely basalt or altered volcanic rock

Probable basalt (fine-grained mafic silicate rock), possibly epidote/chlorite-altered

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Epidotite (Unakite-related)

Epidote-rich rock

Quartz-rich pegmatite with red feldspar or garnet inclusions

Granitoid pegmatite; chiefly quartz and feldspar, with possible almandine garnet or iron-oxide inclusions

Quartz-rich breccia or vein quartz with iron staining

Microcrystalline to crystalline SiO₂, likely quartz with iron oxides/hydroxides and altered host rock

Pebble Gravel Mix (Quartzite, Basalt, Chert)

Alluvial River Gravel / Aggregate Clasts

Quartz / Quartzite

Silicon Dioxide (SiO2)

Quartz with Chlorite or Epidote inclusions

Silicon Dioxide (SiO2) with inclusions

Quartz (Milky Quartz / Quartz Specimen)

Silicon Dioxide (SiO2)

Likely tumbled jasper or iron-stained quartzite

Microcrystalline quartz (SiO₂), possibly quartzite with iron-oxide inclusions

Schist

Schist (Foliated Metamorphic Rock)