Rock (Likely Sedimentary)

Banded Gneiss (River Cobble)

Gneiss (a high-grade metamorphic rock)

Chalcedony (Agate/Jasper mix in host rock)

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

Gneiss (likely)

Gneiss

Granite

Granite (Felsic Plutonic Rock)

Quartz (likely a weathered/tumbled piece)

Quartz (SiO₂)

Quartz with Iron Oxide Monzonite or Sandstone contact

Quartz (SiO2) with Limonite/Hematite staining

Granite (Weathered)

Granitic intrusive rock

River Cobble (Basaltic/Andesitic)

Mafic Igneous Porphyritic Rock

Quartz (in a rock matrix)

Quartz (SiO2)

Quartz (likely)

Quartz (SiO2 - Silicon Dioxide)

Sandstone

Arenite (a specific type of sandstone with less than 15% matrix)

Slate with Quartz Vein

Foliated Metamorphic Rock (Mainly Quartz, Muscovite, Chlorite)

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Gneiss (specifically a Banded Gneiss pebble)

Gneiss (High-grade Regional Metamorphic Rock)

River Stone (likely Siltstone or fine-grained Basalt)

Clastic Sedimentary (Siltstone) or Mafic Igneous (Basalt)

Quartz (likely Jasper or Chert variety)

Quartz (SiO₂)

Basalt with Mineral Vein (Cobble)

Basalt (with likely Quartz/Calcite vein)

Quartz (likely Rose Quartz or Milky Quartz based on color)

Quartz (SiO2 - Silicon Dioxide)

Fossilized Shark Tooth (Dermal Denticle or worn tooth fragment)

Elasmobranchii (fossil remains)

Shale

Fissile Mudstone (primarily composed of phyllosilicate minerals like kaolinite, montmorillonite, and illite)

Orange Calcite (Cleavage Rhomb)

Calcite (Calcium Carbonate, CaCO3)

Granite Glacial Erratic

Intrusive Phaneritic Felsic Rock (Granite)

Basalt with Epidote (Porphyry)

Basalt (with inclusions of Epidote/Feldspar)

Basalt (Vesicular)

Basalt (Extrusive Volcanic Rock)

Jasper (likely Lake Superior Jasper)

Jasper (Silicon Dioxide, SiO2)

Greenstone / Quartzite Pebble

Metamorphosed Quartz-rich Rock

Clear Quartz (Rock Crystal Fragments)

Silicon Dioxide (SiO2)

Granite

Granite (High-silica plutonic rock)

Quartzite (River Cobble)

Metamorphic Quartz-rich Rock

Drupa Quartz (Sparkly Drusy Quartz on Matrix)

Crystalline Silicon Dioxide (SiO2) on host rock

Shale (Beach-worn)

Laminated Pelite (primarily clay minerals and quartz)

Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)

Chert (microcrystalline quartz)

Quartzite Pebble (with Iron Inclusions)

Metamorphic Rock (Mainly SiO2)

Fluorite (likely Green Fluorite variant)

Calcium Fluoride (CaF2)

Banded Calcite (often sold as 'Mexican Onyx')

Calcite (Calcium Carbonate, CaCO3)

Gold in Quartz Matrix

Native Gold (Au) with Quartz (SiO2) and Slate/Shale

Micaceous Rock (likely Muscovite Schist/Gneiss or a Muscovite-rich Specimen)

Predominantly Muscovite (KAl2(AlSi3O10)(F,OH)2), often found in rocks like Muscovite Schist or Muscovite Gneiss.

Chalcedony (Yellow Agate/Chert)

Silicon Dioxide (SiO2)

Chalcedony (Common Agate pebble)

Silicon Dioxide (SiO2)

Calcite (or Alabaster, if truly carved)

Calcium Carbonate (CaCO3)

Peridotite (Dunite)

Peridotite (mostly Olivine: (Mg,Fe)2SiO4)

Druzy Quartz Geode (likely Smokey Quartz variety)

Silicon Dioxide (SiO2) - specifically a geode formation lined with druzy quartz crystals, with a likely brownish hue indicating smokey quartz.