Mineral (Man Modified)

Water-worn pebble, likely fine-grained volcanic rock

Unidentified mafic volcanic rock; possibly andesite or basalt

Polished dendritic agate or jasper

Microcrystalline quartz (chalcedony), SiO₂, with iron/manganese oxide and possibly calcite veins

Dark gray crystalline rock, possibly basalt

Basalt (tentative; plagioclase–pyroxene–iron oxide assemblage)

White quartz pebbles

Quartz, SiO₂ (likely milky quartz)

Ironstone concretion (possibly a pyrite-bearing concretion)

Iron-oxide-cemented sedimentary concretion; exact mineral composition cannot be confirmed from the photograph

Druzy quartz on matrix

Quartz (SiO₂), microcrystalline crystal coating

Tumbled greenstone (likely serpentine or jade-like stone)

Likely serpentine-rich serpentinite; exact identification is not possible from the image alone

Pink calcite

Calcite (CaCO₃), likely manganese-bearing

Dark, coarse-grained rock (possibly mafic igneous rock)

Undetermined; potentially basaltic or gabbroic material

Likely weathered stone or mineral fragment

Unidentified fine-grained silicate rock; possible basalt, greenstone, or serpentine

Likely serpentinized ultramafic rock (serpentinite)

Serpentinite; chiefly serpentine-group minerals, Mg₃Si₂O₅(OH)₄, possibly with magnetite, chromite, and brucite

Quartz with Chlorite or Epidote inclusions

Silicon Dioxide (SiO2) with inclusions

Tumbled amethyst-bearing quartz

Quartz, SiO₂; purple coloration from iron-related defects and irradiation

Black-and-white banded pebble (likely gneiss or migmatite)

Undetermined banded metamorphic rock; mineral composition cannot be confirmed from the image

Granite

Granite — a coarse-grained felsic intrusive igneous rock, typically composed of quartz, feldspar, and mica

Polished Jasper

Cryptocrystalline quartz, SiO2

Quartz-rich rock, likely milky quartz vein material

Quartz (SiO₂), possibly with iron-oxide staining and minor associated minerals

Rough Apatite in Matrix

Fluorapatite / Chlorapatite / Hydroxylapatite (Ca5(PO4)3(F,Cl,OH))

Serpentine

Antigorite, Lizardite, or Chrysotile; (Mg, Fe)3Si2O5(OH)4

Coarse-grained granite pegmatite

Granitic pegmatite; mainly quartz (SiO₂), feldspar, and mica

Small brown mineral fragment

Unidentified; the image lacks enough detail for a reliable species-level identification

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Vesicular basalt (likely weathered lava rock)

Vesicular basalt; primarily plagioclase feldspar, pyroxene, and volcanic glass, with possible iron-oxide alteration

Tumbled brown quartz crystal (likely smoky quartz or iron-stained quartz)

Quartz, silicon dioxide (SiO₂)

White quartz (likely milky quartz)

Quartz, silicon dioxide (SiO₂)

Tumbled garnet-bearing rock, likely garnet schist

Garnet (typically almandine, Fe₃Al₂(SiO₄)₃) in a quartz–mica matrix; exact identification is uncertain from the photo

Polished serpentine pebble

Serpentinite, dominated by serpentine-group minerals (antigorite, lizardite, or chrysotile)

Likely milky quartz

Quartz (silicon dioxide, SiO₂)

Rose quartz (likely rough specimen)

Quartz, silicon dioxide (SiO₂), pink variety

Quartz-rich rock, likely milky quartz or quartz vein fragment

Quartz (silicon dioxide, SiO₂), possibly with minor feldspar or calcite

Iron-stained quartz-rich rock, possibly quartz vein material

Quartz (SiO₂) with iron-oxide staining; host rock not identifiable from the image

Tumbled brown jasper

Microcrystalline quartz (chalcedony), SiO₂; likely jasper

Vesicular basalt

Basalt, predominantly plagioclase feldspar, pyroxene, and olivine; vesicles may contain secondary minerals

Rounded iron-rich pebble

Likely ferruginous sandstone or ironstone; exact identification is uncertain from the photograph

Goethite

Goethite (α-FeO(OH))

Likely basalt

Mafic volcanic rock, chiefly plagioclase and pyroxene, commonly with minor olivine and magnetite

Polished quartz-rich pebble, possibly milky quartz with a dark mineral band

Quartz (SiO₂), with an unidentified dark inclusion or attached matrix

Sea stacks and coastal cliffs

Likely basaltic sea stacks (rock type cannot be confirmed from the image)

Greenish Metamorphic Rock (likely containing epidote or chlorite)

Metamorphic rock, possibly epidosite or greenstone

Likely iron-rich metamorphic rock (possibly hematite-rich ironstone)

Unidentified ferruginous rock; exact mineralogy cannot be determined from the image

Quartz Vein in Rhyolite

Silicon Dioxide (SiO2) in extrusive igneous rock

Likely milky quartz fragment

Quartz (silicon dioxide, SiO₂), possibly with iron-oxide or mica inclusions