Indeterminate

Fossilized bivalve or brachiopod fragment

Indeterminate fossil shell, likely calcitic or aragonitic carbonate

Unidentified rock fragments

Indeterminate; likely a weathered, iron-stained silicate rock

Likely fossilized coral fragment

Rugose or tabulate coral fossil; exact taxon indeterminate

Metallic sulfide ore fragment, possibly pyrite-bearing rock

Indeterminate; likely pyrite (FeS₂) in a sulfide-rich matrix

Tumbled blue-gray mineral specimen

Indeterminate; possibly dumortierite quartz, sodalite, or dyed stone

Small polished dark mineral or gemstone fragment

Indeterminate; possibly smoky quartz, obsidian, or dark tourmaline

Weathered brown stone, likely basalt or iron-stained volcanic rock

Indeterminate; possibly vesicular basalt (mafic silicate rock)

Fossil bone fragment, likely mammalian

Fossilized bone; exact taxon indeterminate from image

Weathered stone, likely sandstone or altered volcanic rock

Indeterminate; possibly quartz-rich sandstone or weathered tuff

Fossil-bearing limestone, possibly a crinoid or shell fragment

Calcite (CaCO₃) limestone containing an indeterminate marine fossil

Tumbled tan stone, possibly sandstone or weathered limestone

Indeterminate; likely quartz-rich sandstone or calcitic limestone

Small gray stone, possibly granite or quartz-rich pebble

Indeterminate; likely a weathered quartz–feldspar rock fragment

Likely polished dark metallic mineral specimen

Indeterminate from image; possibly hematite, magnetite, or galena

Likely dark rounded stone or mineral fragment

Indeterminate; possibly a water-worn mafic rock such as basalt

Fossilized tooth, likely a mammalian tooth fragment

Indeterminate fossil tooth; possibly an ungulate or carnivoran tooth

Likely weathered quartz-rich stone

Indeterminate; possibly quartz-bearing granite or milky quartz

Weathered dark rock fragment

Indeterminate; possibly basalt or iron-rich volcanic rock

Small rounded pebble, likely quartz-rich river stone

Indeterminate; likely quartz/chert-bearing lithic clast

Fossil shell fragment, likely brachiopod or bivalve

Indeterminate fossilized carbonate shell; possibly Spiriferida (brachiopod)

Rounded gray pebble

Indeterminate; likely a water-worn silicate or carbonate pebble

Greenish translucent mineral fragment

Indeterminate; possibly serpentine, epidote, or green glassy feldspar

Likely weathered brown rock fragment

Indeterminate; possibly basaltic or iron-stained mafic rock

Unidentified weathered rock, possibly quartz-bearing granite or rhyolite

Indeterminate; likely quartz–feldspar-rich silicate rock

Fossil shell fragment (likely brachiopod or bivalve)

Indeterminate fossilized carbonate shell; likely Brachiopoda or Bivalvia

Polished agate/jasper pebble

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide staining

Basalt pebble

Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine or iron oxides

Dark gray-brown stone, likely basalt or fine-grained volcanic rock

Basalt (tentative; likely plagioclase–pyroxene rock)

Orange chalcedony / agate fragment

Microcrystalline quartz (SiO₂), likely iron-stained chalcedony

Small rounded pebble, possibly quartz-rich stone

Indeterminate; likely quartz/quartzite or a weathered feldspathic pebble

Unidentified polished mineral specimen

Indeterminate; likely a pale feldspar or quartz-bearing material

Weathered quartz-rich rock, likely granite or gneiss

Indeterminate granitic rock; mainly quartz, feldspar, and mica

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

Indeterminate lithic clast; possible quartz–feldspar aggregate

Ammonite fossil

Ammonoidea (coiled cephalopod fossil; exact genus indeterminate)

Likely tumbled brown stone

Indeterminate; possibly jasper, chert, or iron-stained quartzite

Rounded brown river pebble

Indeterminate; likely weathered sandstone or iron-stained quartzite

Unidentifiable embedded dark fragment

Indeterminate; possibly a dark silicate mineral or lithic inclusion

Likely weathered iron-rich rock fragment

Indeterminate; possibly limonite/goethite-bearing sandstone or ironstone

Fossilized bone fragment (probable vertebrate bone)

Permineralized bone; exact taxon indeterminate from the image

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

Indeterminate; possibly weathered basalt, with hematite/goethite staining

Fossil shell fragment, likely bivalve or brachiopod

Indeterminate fossilized mollusk/brachiopod; commonly calcite (CaCO₃)

Small rough mineral/rock fragment

Indeterminate; possibly quartz-bearing rock or weathered feldspar

Small rounded brown stone, likely weathered iron-rich rock

Indeterminate; possibly ferruginous sandstone, ironstone, or weathered basalt