Uncertain

Mixed gemstone specimens

Likely pink sapphire or tourmaline, red garnet, blue sapphire, precious opal, and green tourmaline/emerald; exact identities cannot be confirmed from the collage

Likely iron-rich river cobble (weathered basalt or ironstone)

Indeterminate; possibly weathered basalt, with hematite/goethite staining

Vesicular basalt (likely scoria)

Basaltic volcanic rock; primarily plagioclase, clinopyroxene, olivine, and volcanic glass

Tumbled quartzite (probable)

Quartzite, predominantly crystalline SiO₂

Iron-rich flint or chert fragment

Microcrystalline quartz (SiO₂), likely ferruginous chert

Tumbled cat’s-eye stone, likely cat’s-eye glass or imitation

Undetermined; natural chrysoberyl cat’s-eye is BeAl₂O₄, but the photo does not establish that identity

Polished star-shaped gemstone, likely black obsidian

Obsidian (volcanic glass), predominantly SiO₂

Tumbled basalt pebble

Basalt, a fine-grained mafic volcanic rock

Possible aquamarine (beryl) crystal fragment

Beryl, Be₃Al₂Si₆O₁₈; green-blue color may indicate aquamarine

Iron-stained quartz-rich rock, possibly goethite-bearing quartz

Quartz (SiO₂) with iron oxides/hydroxides, likely goethite or limonite

Unidentified dark, coarse-grained rock

Possibly diorite or gabbro; identification is uncertain from the image

Small rounded pebble, likely granite or granitic gneiss

Granitoid rock; exact identification is uncertain from the photograph

Faceted black gemstone, likely black spinel

Spinel (MgAl₂O₄); identification from the image is uncertain

Dark, vesicular volcanic rock (likely basalt or scoria)

Vesicular basalt; exact identification is uncertain from the photograph

Quartz-rich pebble, possibly agate or chalcedony

Microcrystalline quartz (SiO₂), identification uncertain from the image

Pale green tumbled stone, possibly green calcite

Uncertain from the image; appearance is consistent with calcite (CaCO₃)

Likely foliated metamorphic rock

Uncertain from the image; possibly mica schist or gneiss

Likely sandstone pebble

Quartz-rich sandstone (composition uncertain from the image)

Pale green mica-rich rock (possibly chlorite schist)

Likely chlorite schist; identification is uncertain from the photograph

Pale green tumbled stone, possibly fluorite

Uncertain from the photo; appearance is consistent with fluorite (CaF₂)

Likely quartz-rich rock (possibly milky quartz or quartz-bearing vein rock)

Quartz, SiO₂; exact identification is uncertain from the image

Small pink-red mineral fragment, possibly ruby or corundum

Corundum (Al₂O₃), unconfirmed; visual identification is uncertain

Pink polished stone fragment, possibly rose quartz

Possibly quartz (SiO₂); identification is uncertain from the image

Rough quartz crystal (possibly smoky quartz)

Quartz, SiO₂; color variety uncertain from the photograph

Possibly iron-stained quartz or chalcedony

Quartz/chalcedony (SiO₂), identification uncertain from the image

Rounded, weathered quartz-rich pebble (likely milky quartz)

Quartz, SiO₂; exact identification is uncertain from the photograph

Pale yellow quartz pebble

Quartz, SiO₂; identification is uncertain from the image alone

Tumbled yellow-orange stone, possibly carnelian

Uncertain from the image; possibly chalcedony (microcrystalline SiO₂)

Large rough rock, likely granite or granitic gneiss

Possibly granite; exact identification is uncertain from the photograph

Faceted brown gemstone ring, likely smoky quartz

Smoky quartz (SiO₂), identification uncertain from the image

Likely weathered quartz-rich pebble

Uncertain; possibly granite or quartz-bearing volcanic rock

Rounded quartz-rich pebble

Likely quartz sandstone or quartzite; visual identification is uncertain

Likely weathered quartz-rich rock fragment

Uncertain; possibly quartz sandstone or a pale feldspathic rock

Dark igneous rock, likely basalt or diabase, with a second purplish specimen

Basalt/diabase; exact identification is uncertain from the photograph

Graphite-bearing schist (probable graphite ore)

Graphite (C) in graphitic schist; identification is visual and uncertain

Banded metamorphic rock, likely gneiss or amphibolite

Composition uncertain; probable quartz–feldspar–amphibole assemblage

Beige polished stone tile (likely limestone or marble)

Uncertain; probable calcite-rich limestone or marble (CaCO₃)

Dyed red crystal aggregate, likely quartz or salt

Uncertain; possibly dyed quartz (SiO₂) or halite (NaCl)

Honey-colored quartz-rich stone, possibly chert or chalcedony

Microcrystalline silica (SiO₂), identification uncertain from photograph

Dark mafic rock, possibly basalt with weathered iron staining

Likely basalt; exact identification is uncertain from the photograph

Small metallic mineral fragment, possibly galena or slag-like sulfide

Tentatively galena (PbS), but identification is uncertain from the image

Small rounded pebble, likely quartz-rich sandstone or granitoid fragment

Uncertain; probable quartz/feldspar-bearing lithic pebble