Uncertain

Likely blue glass or synthetic gemstone jewelry

Uncertain; possibly synthetic spinel, cubic zirconia, or blue glass

Weathered iron-rich rock, possibly meteorite

Uncertain; likely goethite/hematite-rich material, with meteorite possibility

Weathered quartz-rich rock, possibly granite or pegmatite fragment

Uncertain; likely quartz–feldspar aggregate, potentially granitic pegmatite

Possible tektite or iron-rich slag-like natural specimen

Uncertain; possibly natural glass (tektite) or magnetite-rich rock

Polished agate or jasper cabochon (uncertain)

Microcrystalline quartz, SiO₂ (likely chalcedony/agate or jasper)

Polished agate or chalcedony slice (uncertain)

Microcrystalline quartz, SiO₂; possibly fossil-bearing chalcedony

Fluorescent calcite (probable)

Calcite, calcium carbonate (CaCO₃)

Faceted clear gemstone, likely quartz or glass imitation

Most likely quartz (SiO₂); exact identification requires refractive-index and hardness tests

Likely tumbled greenstone (identity uncertain)

Greenstone: metamorphosed mafic volcanic rock, commonly composed of chlorite, actinolite, and epidote

Native silver (likely)

Silver, Ag; possibly silver-bearing sulfide or mica contamination

Tumbled turquoise (likely matrix-bearing)

Turquoise, hydrated copper aluminum phosphate: CuAl₆(PO₄)₄(OH)₈·4H₂O

Migmatitic gneiss

Felsic banded gneiss, commonly quartz–feldspar–biotite ± amphibole

Tumbled orange chalcedony or carnelian

Microcrystalline quartz (SiO₂), commonly iron-stained chalcedony; carnelian variety

Fine-grained gray stone, possibly slate

Slate (fine-grained metamorphosed mudstone); identification is uncertain from the image

Green tumbled agate (likely green chalcedony)

Chalcedony, microcrystalline quartz (SiO₂); exact identification is uncertain from the photo

Banded gneiss

Quartz–feldspar–biotite gneiss (exact minerals uncertain from the photo)

Likely granitic or dioritic pebble

Coarse-grained granitoid (exact identification uncertain from the small image)

Iron-stained quartz crystal cluster

Quartz (SiO₂), likely iron-oxide-stained; exact variety uncertain

Dark, fine-grained rock fragment (possibly basalt)

Basalt, a plagioclase–pyroxene volcanic rock; identification is uncertain from the photo

Greenish translucent mineral fragment, possibly aventurine quartz or fluorite

Uncertain from image; likely quartz (SiO₂) with inclusions, or fluorite (CaF₂)

Likely weathered quartz-rich rock (possibly quartzite or milky quartz pebble)

Quartzite; predominantly quartz (SiO₂), but exact identification is uncertain from the photograph

Tumbled cream-colored stone, likely calcite or quartzite

Most consistent with massive calcite (CaCO₃), though visual identification is uncertain

Tumbled brown quartzite or chert pebble

Quartzite, primarily microcrystalline SiO₂; exact identification is uncertain from the photograph

Colorless faceted gemstone (likely glass or cubic zirconia)

Likely cubic zirconia, ZrO₂; exact identification is uncertain from the photograph

Tumbled quartz-rich pebble, likely quartzite or chert

Quartz (SiO₂), possibly quartzite; exact identification is uncertain from the image

Likely tumbled brown agate or jasper

Microcrystalline quartz, SiO₂ (chalcedony; exact identification uncertain from the photo)

Tumbled brown agate or jasper

Microcrystalline quartz (chalcedony), SiO₂; exact variety uncertain from the image

Fossilized coral fragment

Agatized or silicified coral, likely *Hexagonaria* (identification uncertain from photo)

Black stone bead bracelet

Likely black tourmaline (schorl), though identification is uncertain from the image

Dark rounded stone, likely basalt pebble

Basalt, predominantly plagioclase and pyroxene; exact identification is uncertain from the image

Polished selenite (satin spar gypsum), likely carved/tumbled

Gypsum, CaSO₄·2H₂O; varietal identification is uncertain from the image

Tumbled cream-colored stone, likely quartz or chalcedony

Microcrystalline quartz (chalcedony), SiO₂; exact identification is uncertain from the image

Magnetite (lodestone), possibly meteoritic iron

Magnetite, Fe₃O₄; exact identification is uncertain from the image alone

Pseudometeorite ironstone or weathered metallic nodule

Uncertain; likely iron-oxide-rich limonite/goethite with magnetite or hematite

Polished green-inclusion stone, likely chlorite-included quartz

Quartz (SiO₂) with chlorite inclusions; exact identification is uncertain from the photograph

Weathered quartz-rich rock, possibly quartzite or granitic pegmatite fragment

Quartz (SiO₂)-dominant aggregate; exact identification is uncertain from the photograph

Small green mineral specimen, possibly aventurine or serpentine

Uncertain; likely quartz-bearing aventurine (SiO₂) or serpentine-group mineral

Likely biotite-bearing granite or granitic gneiss

Quartz–feldspar–biotite aggregate; exact identification is uncertain from the photograph

Weathered quartz-rich rock, possibly chert or quartzite

Likely microcrystalline quartz (SiO₂), but exact identification is uncertain from the photograph

Pale weathered pebble, likely limestone

Limestone, predominantly calcite (CaCO₃); exact identification is uncertain from the image

Polished gray pebble, likely quartzite or fine-grained granite

Probable quartzite (mostly microcrystalline SiO₂); identification is uncertain from the photograph

Tumbled quartz-rich stone, possibly chert or quartzite

Quartzite (mostly SiO₂), though precise identification is uncertain from the image