Undetermined

Small quartz-rich rock fragment (possibly weathered quartz vein material)

Quartz (SiO₂) in an undetermined host rock; the image is insufficient to identify the host confidently

Banded metamorphic rock, likely gneiss or banded amphibolite

Undetermined foliated metamorphic rock; commonly quartz–feldspar–biotite gneiss or amphibolite

Weathered iron-rich rock, possibly limonite-bearing basalt or ironstone

Undetermined; likely iron oxides/hydroxides (goethite–hematite–limonite) in a silicate host

Unknown brown-and-gold rock fragment

Undetermined; possibly iron-stained quartz, mica schist, or sulfide-bearing ore

Green faceted gemstone, likely synthetic glass or chrome-dyed stone

Undetermined; possibilities include green tourmaline, synthetic emerald, glass, or dyed quartz

Iron-rich brown stone, possibly weathered chert or ironstone

Undetermined; likely iron-oxide-bearing silica-rich rock (chert/ironstone)

Small blue-gray mineral fragment (undetermined)

Unidentified from the image; no reliable mineral identification is possible from color and appearance alone.

Small tan mineral or rock fragment (undetermined)

Unidentified; the image does not provide enough detail for a reliable identification

Rounded brown pebble (rock type undetermined)

Unidentified, iron-stained lithic pebble; composition cannot be determined from the photograph

Colorless faceted gemstone, possibly quartz

Undetermined; appearance is consistent with colorless quartz (SiO₂), but identification from the image alone is uncertain

Rounded, weathered metamorphic rock (likely quartz-rich gneiss or schist)

Undetermined; likely quartz–feldspar-rich gneiss, with possible mica and iron-oxide staining

Dark green-black tumbled stone, possibly nephrite jade

Undetermined; possible nephrite (tremolite–actinolite, Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂)

Dark, coarse-grained rock; likely gabbro or diorite

Undetermined mafic-to-intermediate intrusive igneous rock; exact identification requires closer examination

Green copper-bearing rock, possibly chrysocolla-bearing matrix

Undetermined copper-mineralized rock; green areas may include chrysocolla, malachite, or chlorite

Small gray-green stone, likely a quartz-rich rock fragment

Undetermined silicate rock; image lacks enough detail for a reliable species-level identification

Carved yellow stone butterfly

Undetermined; possibly carved soapstone (talc-rich rock) or another soft ornamental stone

Dark, coarse-grained rock fragment (possibly amphibolite or gabbro)

Undetermined; amphibolite commonly contains hornblende and plagioclase, while gabbro contains plagioclase and pyroxene

Small polished, multicolored stone; exact identification is not possible from the image

Undetermined; it may be a naturally patterned stone such as jasper, but the visible colors alone are insufficient for identification

Rounded green-gray pebble, possibly serpentinite

Undetermined; appearance is consistent with serpentine-rich rock, but a photograph cannot confirm the mineral identification

Blue faceted gemstone, likely synthetic spinel or sapphire

Undetermined from image; possible synthetic corundum (Al₂O₃) or spinel (MgAl₂O₄)

White pebbles (rock material not identifiable from the image)

Undetermined; the smooth, pale pieces could be quartz, quartzite, or another light-colored rock

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

Likely assorted beach/river pebbles

Undetermined mixed lithologies; visible pieces may include quartz-rich and volcanic rocks

Iron-rich meteorite candidate

Undetermined stony-iron or iron meteorite; mineralogy likely Fe–Ni metal with silicates

Weathered iron-rich rock, possibly basalt or limonite-bearing sandstone

Undetermined; likely Fe-oxide-stained basalt or ferruginous sandstone (hematite/goethite-bearing)

Iron-rich meteorite candidate

Undetermined meteoritic iron–nickel material; possibly an ordinary chondrite or weathered iron meteorite

Iron-rich meteorite candidate

Undetermined; possible stony-iron or iron meteorite, commonly kamacite–taenite (Fe–Ni)

Tumbled brown stone, possibly bronzite

Undetermined; appearance may be consistent with bronzite, an iron-bearing orthopyroxene ((Mg,Fe)₂Si₂O₆)

Tumbled olive-green stone, possibly serpentine or nephrite jade

Undetermined; likely serpentine (Mg₃Si₂O₅(OH)₄) or nephrite, a tremolite–actinolite amphibole aggregate

Tiny metallic mineral grain (possibly native silver or a metallic sulfide)

Undetermined from the photograph; native silver (Ag) is one possibility, but identification requires examination or testing

Backlit translucent mineral specimen, possibly amber or orange calcite

Undetermined; visual appearance alone cannot distinguish amber from calcite or other translucent minerals

Rounded pebble, likely quartz-rich

Undetermined quartz-rich lithic pebble; exact rock type cannot be identified from the photograph

Green tumbled stone, possibly serpentine

Undetermined; appearance is consistent with serpentine-rich rock (serpentinite), but the image alone cannot confirm identification.

Tumbled pale-green stone, possibly jade or serpentine

Undetermined; jadeite (NaAlSi₂O₆) or nephrite (Ca₂(Mg,Fe)₅Si₈O₂₂(OH)₂) are possibilities

Mixed mineral and rock specimens

Undetermined assortment; individual pieces may include quartz, feldspar, mica, and other common minerals

Green faceted or cabochon gemstone (possibly glass or synthetic)

Undetermined; possibilities include green beryl (Be₃Al₂Si₆O₁₈), quartz (SiO₂), or synthetic glass

Quartz-rich rock, likely granite or quartz-bearing metamorphic rock

Undetermined; possibly granitic rock composed mainly of quartz and feldspar, with mica or other dark minerals

Red gemstone ring; likely synthetic ruby or red glass

Undetermined from the image; ruby is corundum (Al₂O₃), while red glass is amorphous silicate

Dark gray river pebble

Undetermined fine-grained mafic or intermediate rock; composition cannot be identified reliably from the image

Blue-gray stone fragment, possibly slate or fine-grained basalt

Undetermined; appearance is consistent with slate (fine-grained metamorphosed mudstone), but the image is insufficient for reliable identification.

Green faceted gemstone earrings

Undetermined; possibly green glass or synthetic emerald-type material, rather than identifiable natural emerald

Iron-stained quartz vein rock

Quartz-rich rock with iron-oxide/hydroxide coatings (hematite/goethite); exact host rock undetermined