Uncertain

Agatized fossil fragment, possibly silicified coral

Chalcedony (microcrystalline SiO₂) replacing carbonate fossil material

Polished copper-bearing mineral specimen, likely malachite-rich copper ore

Malachite, Cu₂CO₃(OH)₂, possibly mixed with chrysocolla or limonite

Mixed collection of tumbled minerals and rough specimens

Multiple species visible; likely fluorite, quartz/chalcedony, pyrite, tiger’s eye, rose quartz, and possibly labradorite or agate

Pink-and-gray quartz-rich pegmatite, possibly rose quartz with feldspar

Quartz (SiO₂) with K-feldspar/plagioclase; likely pegmatitic granite

Pyrite-bearing sulfide specimen

Pyrite (FeS₂), possibly with chalcopyrite and weathered sulfides

Amazonite-bearing feldspar (likely raw amazonite)

Amazonite, a blue-green variety of microcline feldspar; KAlSi₃O₈

Weathered sandstone or siltstone cobble

Clastic sedimentary rock, probably quartz-rich sandstone; exact identification requires testing

Likely rough blue-green beryl (aquamarine)

Beryl, Be₃Al₂Si₆O₁₈; blue-green color is caused mainly by iron

Polished/polished rough quartz crystal, likely hematoid or included quartz

Quartz (SiO₂), with probable iron-oxide inclusions; possibly smoky or rose-tinted quartz

Tumbled quartz crystal, possibly rose quartz

Quartz (SiO₂), likely iron- or manganese-tinted varieties

Weathered feldspar-rich rock, possibly amazonite-bearing granite

Likely granite or pegmatite containing microcline feldspar (KAlSi₃O₈), with quartz and altered minerals

Polished black stone, likely black obsidian

Obsidian (volcanic glass), predominantly rhyolitic silica glass

Polished ocean jasper (orbicular jasper)

Microcrystalline quartz/chalcedony (SiO₂) with iron-oxide and other mineral inclusions

Likely jasper or iron-rich chert

Microcrystalline quartz (SiO₂), commonly colored by iron oxides

Rounded sandstone pebble

Quartz-rich sandstone (likely arkose or lithic sandstone)

Rounded granite cobble

Granite, likely biotite granite or granodiorite

Blue apatite (likely dyed or enhanced)

Apatite group; fluorapatite, Ca5(PO4)3F, is the common blue variety

Rounded pebble, likely limestone

Microcrystalline calcite (CaCO₃), probably micritic limestone

Tumbled turquoise (probable)

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

Copper-bearing quartz/rock fragment with attached mica

Chalcopyrite-bearing quartz or altered igneous rock; attached flake likely muscovite or biotite mica

Weathered gray granitic rock

Likely granite or granodiorite; quartz, feldspar, and mica-rich silicate rock

Weathered granite, possibly pink granite

Granite; chiefly quartz, alkali feldspar, plagioclase, and biotite/hornblende

Quartz-rich weathered rock, possibly quartz geode or vuggy quartz vein

Quartz (SiO₂), likely with iron-oxide staining and possible feldspar/calcite matrix

Polished fossil-bearing limestone

Fossiliferous micritic limestone, likely containing gastropod or ammonoid fragments

Sandstone masonry blocks

Clastic sandstone, primarily quartz (SiO₂) with feldspar and lithic grains

Micaceous schist

Mica schist, chiefly muscovite/biotite with quartz and feldspar

Quartz-rich gravel fragment

Quartz (silicon dioxide, SiO₂), possibly with feldspar or carbonate inclusions

Likely weathered basalt or mafic volcanic rock

Basalt; chiefly plagioclase feldspar, pyroxene, and possibly olivine

Tumbled, weathered limestone or calcareous concretion

Calcite-rich limestone; predominantly calcium carbonate (CaCO₃)

Dark gray-green fine-grained rock, likely basalt

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

Likely rough pink feldspar or rose quartz

Most likely microcline feldspar (KAlSi₃O₈) or rose quartz (SiO₂)

Graphite-bearing metamorphic rock (probable graphite schist)

Graphite schist; predominantly quartz–mica–graphite, with possible feldspar and sulfide minerals

Red jasper / iron-rich chert

Microcrystalline quartz (SiO₂), commonly colored by hematite or goethite

Tumbled yellow jasper or petrified wood fragment

Microcrystalline quartz (chalcedony), SiO₂, possibly iron-oxide-bearing jasper

Faceted brown gemstone ring, likely smoky quartz

Smoky quartz (SiO₂), identification uncertain from the image

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)

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