Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated iron(III) oxide-hydroxide)
mineral
Category
Sedimentary Or Metamorphic (Base Substrate)
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Amethyst and Calcite collection
Silicon Dioxide (SiO2) and Calcium Carbonate (CaCO3)
mineral
Sandstone Beach Pebble
Clastic Sandstone (SiO2 - Quartz-dominant)
sedimentary
Quartzite River Stone
Metamorphic Quartzite (primarily SiO2)
metamorphic
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartz River Pebble
Silicon Dioxide (SiO2)
mineral
Mixed mineral and rock collection
Predominantly quartz varieties, including amethyst, plus likely calcite, feldspar, mica, and miscellaneous polished stones
mineral
Mixed collection of common river stones
Varied lithologies, visibly including quartz-rich rock, dark mafic rock, sandstone, and purple quartz-bearing material
igneous, sedimentary, metamorphic
Note: Item is a Synthetic/Man-made Object
Titanium-coated Stainless Steel (Fe-Cr-Ni-Ti)
Non-geological
Zoisite with Ruby
Anyolite (Calcium aluminum hydroxy silicate with Corundum) Ca2Al3(SiO4)3(OH)
metamorphic
White Agate / Chalcedony
Silicon Dioxide (SiO2)
gemstone
Red Sandstone (Old Red Sandstone Pebble)
Arenite with iron oxide (Fe2O3) cement
sedimentary
Quartzite with Mica / Gneiss Pebble
Metamorphic Rock (Quartz-Feldspar-Mica aggregate)
metamorphic
White Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Limonite or Goethite (Ironstone)
Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)
mineral
Banded River Cobble (Argillite or Shale)
Laminated Mudstone / Argillite
sedimentary
River Stone (Chert/Siltstone)
Cryptocrystalline Quartz (SiO2) with trace impurities
sedimentary
White Sapphire
Corundum (Al2O3)
mineral
Carnelian
SiO2 (Silicon Dioxide with Iron Oxide impurities)
gemstone
Potassium-Rich Silicate Clay (inferred from biological context)
Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)
mineral
Cordierite (Iolite) in Quartz
Cordierite (Magnesium iron aluminium cyclosilicate) - Mg2Al4Si5O18
metamorphic
Green Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Quartz-rich limestone or calcitic marble
Calcite (CaCO₃), possibly with quartz (SiO₂)
metamorphic
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Sandstone (River Pebble)
Quartz Arenite / Lithic Sandstone
sedimentary
Chalcedony (Agate) Pebble
Silicon Dioxide (SiO2)
mineral
Red Jasper
Silicon Dioxide (SiO2) with Hematite (Fe2O3) inclusions
sedimentary
Yellow Aventurine
Silicon Dioxide with inclusions (SiO2 + Muscovite/Fuchsite)
mineral
Oak-grain Laminate (Industrial/Decorative Furniture Finish)
Melamine Resin-impregnated Decorative Paper on Particleboard (Cellulose/Thermosetting Plastic)
not a rock (synthetic material)
Red Shale
Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)
sedimentary
Quartz Vein in Sedimentary Matrix
Silicon Dioxide (SiO2) with host rock
mineral
Colorless Quartz (Rhinestone)
Silicon Dioxide (SiO2)
mineral
Basalt River Pebble
Aphanitic mafic volcanic rock
igneous
Basalt (Beach Pebble)
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Yellow Apatite
Fluorapatite (Ca5(PO4)3(F,Cl,OH))
mineral
Aragonite Star Cluster
Aragonite (Calcium Carbonate - CaCO3)
mineral
Smooth river pebble
Indeterminate lithology; likely fine-grained quartz-rich sandstone, siltstone, or weathered chert
sedimentary
Tumbled hematite (likely hematite-rich ironstone)
Hematite, Fe₂O₃; possibly mixed with magnetite or goethite
mineral
Native Silver Nugget
Silver (Ag)
mineral
Laterite
Laterite (Iron/Aluminum-rich oxide)
sedimentary
Mica
Mica group (often Muscovite or Biotite)
mineral