River Cobble (likely Basalt or Metagraywacke)
Non-specific water-worn lithic fragment
igneous or metamorphic
Category
Igneous Or Metamorphic
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Moonstone
Orthoclase Feldspar (KAlSi3O8)
Mineral
Quartz
Silicon dioxide (SiO2)
Mineral
Orange Quartz with Hematite inclusions
Quartz (SiO2) with Hematite (Fe2O3) inclusions
Mineral
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
mineral
Biotite Mica
Biotite, K(Mg,Fe)3AlSi3O10(F,OH)2
mineral
Granite or Granitic Gneiss Pebble
Granite (felsic intrusive igneous rock) or Gneiss
Igneous or Metamorphic
Smoky Quartz
Quartz (SiO₂)
Mineral
Green Tourmaline (Verdelite)
Tourmaline Group; often Elbaite (Na(Li,Al)3Al6(BO3)3Si6O18(OH)4) or Dravite (NaMg3Al6(BO3)3Si6O18(OH)4)
Mineral
Snowflake Obsidian and Green Aventurine
Volcanic Glass (SiO2 with Cristobalite inclusions) and Quartz (SiO2 with Fuchsite)
igneous and metamorphic
Granitic Pegmatite Intrusion in Host Rock
Pegmatite dike in amphibolite or schist
igneous and metamorphic
Granite or Granitic Gneiss River Rock
Granite / Gneiss
Igneous or Metamorphic
Glacial Cobbles (predominantly Granite and Gneiss)
Mixed lithologies (Quartz, Feldspar, Mica assemblage)
igneous and metamorphic
Rose Quartz
Rose Quartz (SiO2)
mineral
Glacially transported granite and gneiss boulders
Granite (quartz–feldspar–mica); banded specimens likely gneiss
igneous and metamorphic
Black Tourmaline (Schorl)
Schorl (Na(Fe^2+)3Al6(Si6O18)(BO3)3)(OH)3(OH))
mineral
Rock Crystal Quartz
Quartz (SiO₂)
Mineral
Rutilated Quartz
Quartz (SiO2) with Rutile (TiO2) inclusions
Mineral
Aventurine
Aventurine Quartz (SiO2 with inclusions)
Mineral
Hematite
Hematite (Fe2O3)
mineral
Black Tourmaline (Schorl)
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
mineral
Biotite Mica
K(Mg,Fe2+)3(Al,Fe3+)Si3O10(OH,F)2
Mineral
Green Aventurine (likely)
Silicon dioxide (SiO2) with fuchsitemica inclusions
Mineral (specifically a variety of Quartz)
Green Aventurine
Quartz (SiO2) with Fuchsite inclusions
Mineral
Green Aventurine
Aventurine (a variety of Quartz, SiO2 with fuchsite inclusions)
Mineral
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(OH)₄(BO₃)₃Si₆O₁₈)
Mineral
Citrine Quartz
Quartz (SiO2) - specifically, a variety of macrocrystalline quartz
Mineral
Rutilated Quartz
Quartz (SiO2) with Rutile (TiO2) inclusions
Mineral
Moonstone
Adularia (orthoclase feldspar variety)
mineral
Quartz (milky quartz variety)
Quartz (SiO₂)
Mineral
Diopside (likely Chromian Diopside)
Diopside, part of Clinopyroxene family of inosilicates. Chemical formula: CaMgSi2O6. The green variety is often Chromian Diopside due to chromium impurities.
mineral
Pyrite
Pyrite (FeS2)
Mineral
Smoky Quartz
Smoky Quartz (SiO ₂)
Mineral
Aquamarine
Beryl (Be3Al2Si6O18), specifically the blue-green variety
Mineral
Quartz
Silicon Dioxide (SiO2)
Mineral
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄)
Mineral
Citrine
Quartz (SiO2) - specifically, a variety of macrocrystalline quartz
mineral
Tourmaline (likely Schorl)
Tourmaline Group Mineral (e.g., Schorl for black varieties); (Na,Ca)(Li,Mg,Fe,Mn,Al)3Al6(BO3)3Si6O18(OH)4
Mineral
Rose Quartz
Rose Quartz (SiO₂)
mineral
Calcite (commonly referred to as Orange Calcite or Honey Calcite given its color)
Calcite
Mineral
Green Aventurine
Aventurine (a variety of Quartz, SiO2)
Mineral
Quartz (likely milky quartz or a stained variety)
Silicon Dioxide (SiO₂)
Mineral