Igneous, Sedimentary, Or Metamorphic (Mineral Based)

Granite

Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gold Nugget

Native Gold (Au)

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Biotite Schist (likely)

Biotite Schist (rock), Biotite (mineral)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Gneiss (specifically a weathered or stream-worn specimen)

Gneiss (Foliated Metamorphic Rock)

Calcite (Yellow/Orange variety - sometimes called Honey Calcite)

Calcite

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Labradorite

Labradorite (a variety of Plagioclase Feldspar), Na(AlSi3O8) to Ca(Al2Si2O8)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Quartz (Milky or Rough Variety)

Silicon Dioxide (SiO2)

Chert (Limestone-based)

Silicon Dioxide (SiO2) within Carbonate host

Chert (Limestone-based)

Silicon Dioxide (SiO2)

Banded Gneiss

Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Mica)

Banded Iron Formation (BIF)

Magnetite-Hematite Chert (Banded Iron Formation)

Gneiss

Gneiss (High-grade metamorphic rock composed primarily of Quartz, Feldspar, and various Micas)

Epidote in Matrix

Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

Fuchsite

Chromium-bearing Muscovite - K(Al,Cr)2(AlSi3O10)(OH)2

Moss Agate

Silicon Dioxide (SiO2) with inclusions

Gneiss (High-Grade Metamorphic Rock)

Gneiss (primarily composed of Quartz, Feldspar, and Mica/Amphiboles)

Beryl (Variety Mix)

Be3Al2(Si6O18)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Mica Schist

Foliated Metamorphic Rock (Schist)

Exposed Aggregate Concrete (Pea Gravel)

Concrete with Siliceous Alluvial Gravels

Conglomerate

Clastic sedimentary rock (Psephite)

Red Mudstone (Siltstone)

Lutite (primarily Quartz and Clay minerals with Hematite)

Conglomerate (Asphaltic/Anthropogenic)

Clastic sedimentary rock / Bituminous mixture

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Limonite streaks)

River Pebble (Likely Chert or Fine-Grained Sandstone/Quartzite)

Siliciclastic clast (likely Chert or Quartzarenite/Quartzite pebble)

Quartz

Silicon dioxide (SiO2)

Schist (Micaceous Schist)

Mica Schist

Green Aventurine

Silicon Dioxide (SiO2) with Chromium-rich Fuchsite mica

Anthracite Coal

Anthracite (Carbon-based organic sedimentary rock exposed to metamorphic heat/pressure; Chemical composition is approximately 86%–98% Carbon)

Quartz Druzy (on Calcedony/Quartz base)

Silicon Dioxide (SiO2)

Jasper and Yellow Chert (Tumbled)

Microcrystalline Quartz (SiO2)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Schist (specifically Chlorite/Greenschist)

Chlorite Schist

Quartz (possibly milky quartz)

Quartz (Silica; SiO₂)

Obsidian

Volcanic glass (high silica content based on SiO2)