Sedimentary (Man Made)

Green Aventurine and Clear Quartz

Aventurine (variety of Quartz - SiO2) and Quartz (SiO2)

Sandstone (likely a river or beach pebble)

Sandstone (a clastic sedimentary rock)

Zebra Jasper (Zebra Stone)

Silicon Dioxide (SiO2) with iron oxide and manganese inclusions

River Pebbles (Sandstone and Quartzite)

SiO2 (Quartz) dominated clastic rocks

Quartz Pebble

Silicon Dioxide (SiO2)

Red Jasper or Chert

Jasper (SiO2, a variety of chalcedony with iron oxide impurities), Chert (SiO2)

Banded Chert

Chert (a microcrystalline variety of quartz, SiO2 with minor impurities)

Sandstone (Pebble/Cobble)

Sandstone (arenite is a more precise term for sandstone with less than 15% matrix; this specimen appears to be a lithic or quartz arenite)

Red Jasper (beads)

Silicon Dioxide (SiO2) with iron inclusions

Limonite (Iron Ore)

Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)

Pyrite

Iron Pyrite (FeS₂)

Dendritic Agate (or Dendritic Opal)

SiO2 (for Agate), SiO2·nH2O (for Opal)

Quartz (likely milky/gray variety)

Quartz (SiO₂)

Yellow Jade (often Serpentine or Dolomite)

Primarily Serpentine (Mg3Si2O5(OH)4) or Dolomite (CaMg(CO3)2), though the term 'yellow jade' is also sometimes applied to varieties of true nephrite or jadeite.

Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone)

Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)

Laterite

Laterite (no specific mineral formula as it's a rock type)

Banded Iron Formation (BIF)

Banded Iron Formation

Quartz (likely Yellow/Orange variety, possibly Citrine or Chalcedony with iron staining)

Quartz (SiO₂)

Jasper with Hematite (Red Jasper)

Silicon Dioxide with Iron Oxide (SiO2 and Fe2O3)

Pebble

Clast (specifically a granule or small pebble)

Banded Iron Formation

Banded Iron Formation (BIF)

Quartz (likely tumbled or naturally water-worn)

Quartz (SiO₂ - Silicon Dioxide)

Fluorite

Fluorite (Calcium Fluoride - CaF2)

Kyanite

Kyanite (Al2SiO5)

Bivalve Shell (Fossil or Contemporary)

Class Bivalvie (various genera and species of clams, cockles, etc.)

Orthoclase Feldspar (or K-Feldspar)

Orthoclase (KAlSi3O8)

Quartz

Silicon dioxide (SiO2)

African Turquoise

Teal Jasper (Macro-crystalline Quartz/Sio2 + Inclusions of Copper, Iron, and Manganese)

Quartz (pebble)

Quartz (SiO₂)

Quartz (likely a clear or rock crystal variety)

Quartz (SiO2 - Silicon Dioxide)

Rock Crystal Quartz

Quartz (SiO₂)

Quartz (possibly milky quartz or quartz with inclusions)

SiO2 (Silicon Dioxide)

Green Calcite

Calcite (CaCO3)

Unidentified Rock Fragment

Unknown

Quartz Geode (partially formed/chalcedony with iron staining)

Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides

Banded Gneiss (River Cobble)

Gneiss (a high-grade metamorphic rock)

Pink Stained Rock (Likely Quartzite or Sandstone with Iron Oxide Staining)

Quartzite (metamorphic) or Sandstone (sedimentary); coloration likely due to hematite or other iron oxides.

Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)

Quartz (SiO₂)

Quartz (on matrix)

Quartz (Silicon Dioxide, SiO₂)

Fossilized Wood (Petrified Wood)

Silicified Wood (primarily quartz/chalcedony replacing organic matter)

Corundum

Corundum (Al2O3)

Kyanite

Kyanite (Al2SiO5)