Igneous And Metamorphic Derivative (Weathered)

Gneiss (Banded Gneiss Cobble)

Gneiss

Quartz Pebble

Silicon Dioxide (SiO2)

Brown Garnet

Andradite or Almandine Garnet (general formula X3Y2(SiO4)3)

Granite or Quartzite Pebble

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Granite Gneiss River Rock

Gneiss

Weathered rock fragment, possibly granite or metamorphic stone

Indeterminate; likely quartz–feldspar–mica aggregate (granite-like), but image resolution prevents reliable identification

Quartz-rich rock, possibly milky quartz or quartzite fragment

Quartz (SiO₂), potentially quartzite if metamorphic

Likely polished bronzite or serpentine-rich rock

Probable bronzite, an iron-bearing orthopyroxene (Mg,Fe)SiO₃; exact identification requires testing

Weathered quartz-rich pebble

Likely quartzite or felsic granitoid fragment; predominantly SiO₂ quartz with minor feldspar and dark iron-bearing minerals

Sapphire

Corundum (Al2O3)

Nephrite Jade (Yellow Skin)

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) in matrix

Rounded quartz-rich pebble

Likely granitoid-derived quartz–feldspar rock; exact identification uncertain from image

River Pebble (Granite/Gneiss)

Granitic Pebble (Quartz, Feldspar, Mica composition)

Likely quartz fragment

Quartz (silicon dioxide, SiO₂), possibly milky quartz or quartz-rich rock

Weathered quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly quartz (SiO₂), with minor iron-oxide staining and possible mica/clay minerals

Quartz-rich metamorphic rock (likely mica schist or gneiss)

Quartz–feldspar–mica assemblage; probable biotite schist/gneiss

Quartz-Tourmaline Pebble

Quartz with Tourmaline inclusions

Nephrite Jade

Ca2(Mg,Fe)5Si8O22(OH)2

Small rounded pebble, likely quartz-rich stone

Indeterminate from photograph; possibly microcrystalline quartz (SiO₂) or a weathered silicate pebble

Milky Quartz (Water-worn pebble/nodule)

Quartz (Silicon Dioxide - SiO2)

Quartz (Milky or Clear variety)

Silicon Dioxide (SiO2)

Weathered quartz-bearing rock, possibly gneiss or quartzite

Indeterminate; likely quartz-rich metamorphic rock containing quartz and feldspar

Garnet (almandine or pyrope variety)

Silicate mineral Group: (Fe, Mg, Mn, Ca)3(Al, Fe, Cr)2(SiO4)3

Likely weathered brown quartz-bearing rock

Tentatively weathered granite or granitic gneiss; exact identification is uncertain from the photograph

Yellow Agate

Agate (Varietal form of Chalcedony/Quartz, SiO2)

Garnet Gneiss or Mica Schist with Garnet

Almandine Garnet-bearing Gneiss

Mixed rock and mineral specimen collection

Mostly undetermined from the photograph; apparent quartz-rich rocks, sandstone, granite/gneiss, and possibly iron-oxide-bearing specimens

Small quartz-rich rock fragment (tentative)

Likely quartz (SiO₂) with possible feldspar or carbonate inclusions

Quartz-rich gravel fragment

Quartz (silicon dioxide, SiO₂), possibly with feldspar or carbonate inclusions

White Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz with inclusions

Silicon Dioxide (SiO2)

Blue Sapphire (Tumbled/Polished)

Corundum (Al2O3)

Quartz pebble

Silicon dioxide (SiO2)

Quartz (Iron-stained or Chalcedony varieties)

Silicon Dioxide (SiO2)

Sapphire

Corundum (Al2O3)

Quartz Pebble (with probable Iron staining)

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)