Siltstone
Siltstone (composed of microscopic quartz and clay minerals)
sedimentary
Category
Organic (Non Rock)
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Note on Image Identification: Textile
N/A (Anthropogenic material)
not a rock
Quartzite River Rock
Quartzite (SiO2)
metamorphic
Polished ornamental jasper (likely Peanut Wood or similar brecciated jasper)
Microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and clay inclusions
mineral
Weathered mafic rock, likely basalt or gabbro
Basalt–gabbroic rock; chiefly plagioclase feldspar and pyroxene, with possible olivine and magnetite
igneous
Quartzite Cobble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Weathered quartz-rich rock, possibly quartzite or iron-stained quartz
Quartzite (mostly SiO₂), with possible iron-oxide staining and minor feldspar/mica
metamorphic
Snowflake Obsidian
Volcanic Glass (spherulitic obsidian)
igneous
Siltstone Pebble
Siltstone (fine-grained siliciclastic sedimentary rock)
sedimentary
Snowflake Obsidian
Volcanic glass (SiO2) with Cristobalite (SiO2) inclusions
igneous
Shale (with Iron Staining)
Argillaceous mudstone / Shale
sedimentary
Sandstone (with potential fossil inclusions)
Clastic sedimentary rock (primarily SiO2)
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Black Mountain Stone (Seiryu Stone)
Limestone with Calcite veins (CaCO3)
sedimentary
Quartzite Pebble
Quartzite (SiO2)
metamorphic
Quartzite with inclusions
Metamorphic Rock (Mainly SiO2)
metamorphic
Bivalve seashell
Calcareous shell, primarily aragonite (CaCO₃); likely a modern cockle or related bivalve
fossil
Chert (Nodule)
Microcrystalline or Cryptocrystalline Silica (SiO2)
sedimentary
Note: This is a Man-Made Object (Costume/Prop Patch)
Synthetic fiber and pigments (Cellulose/Plastic-based composite)
Non-geological
Pebble / Sandstone / Siltstone
Sedimentary Rock (Quartz Sandstone / Siltstone)
sedimentary
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
River Rock (Basalt or Siltstone)
Basalt (Aphanitic Igneous Rock)
igneous
Quartzite
Quartzite (chiefly SiO2)
metamorphic
Quartzite
Quartzite (predominantly SiO2)
metamorphic
Quartzite
Quartzite (SiO2)
metamorphic
Dendritic Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions
mineral
Quartzite
Quartzite (primarily SiO2)
metamorphic
Pink granite or pink feldspathic rock
Granite, chiefly quartz, potassium feldspar, and plagioclase; exact identification is uncertain from the image
igneous
Green Sea Glass
Amorphous Silica (man-made glass), SiO2 + additive metal oxides
mineraloid / anthropogenic (man-made origin)
Quartz-veined Siltstone/Greywacke
Clastic Sedimentary Rock with Quartz Infill (SiO2 vein)
sedimentary
Quartz-veined Limestone
Sedimentary limestone with quartz/calcite veinlets
sedimentary
Black Obsidian
Obsidian (Volcanic glass), 70–75% SiO2
igneous
Fossilized Bone Fragment
Vertebrate Fossil
fossil
Quartzite Pebble
Metamorphic Quartzite (SiO2)
metamorphic
Weathered fossil fragment, possibly bone
Indeterminate fossilized bone; likely mineralized vertebrate bone (apatite-rich)
fossil
Limestone (Tufa/Travertine)
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Fossilized Oyster Shell
Ostreidae (Calcium Carbonate - CaCO3)
fossil
Small pale rock fragment
Indeterminate; possibly quartz, calcite, or a weathered feldspar-rich fragment
mineral
Yellow Quartzite River Stone
Quartzite (SiO2)
metamorphic
Sandstone
Arenite
sedimentary
Chert / Flint
Silicon Dioxide (SiO2)
sedimentary
River-worn Chert
Microcrystalline Quartz (SiO2)
sedimentary