Metamorphic (Man Made)

Dark mafic metamorphic rock, likely amphibolite

Amphibolite; chiefly hornblende amphibole and plagioclase feldspar

Biotite Schist

Biotite Gneissic Schist (K(Mg,Fe)3AlSi3O10(OH)2)

Clear quartz crystal

Quartz (silicon dioxide, SiO₂)

Rounded gray-green rock, likely gneiss

Gneiss (tentative; mineral composition and texture cannot be confirmed from the image)

Tumbled greenstone-like pebble

Likely serpentine or chlorite-rich metamorphic rock; exact identification requires testing

Jade bangle

Likely nephrite jade (actinolite–tremolite amphibole); possibly jadeite

Sandstone (specifically Arkose or Quartz Arenite)

Arenite (primarily SiO2 with possible Feldspar)

Milky quartz

Quartz (silicon dioxide, SiO₂)

Turquoise cabochon ring

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

Milky quartz

Quartz (silicon dioxide, SiO₂)

Amphibolite with Hornblende

Amphibole-rich Metamorphic Rock (Ca2(Mg,Fe)5Si8O22(OH)2)

Rounded, banded metamorphic cobble

Likely gneiss or foliated quartz-rich metamorphic rock; exact identification is uncertain from the photograph.

Red Sandstone

Arenite (with Iron Oxide / Hematite staining)

Calcite (commonly referred to as Orange Calcite or Honey Calcite given its color)

Calcite

Milky quartz vein fragment

Quartz (SiO₂), likely massive or vein quartz with minor iron-oxide/clay inclusions

Tumbled milky quartz

Quartz (SiO₂), microcrystalline or massive variety

Quartz vein in greenstone

Milky quartz (SiO₂) cutting metamorphosed mafic rock, likely greenschist or amphibolite

Quartz-rich rock, likely milky quartz vein material

Mostly quartz (SiO₂); exact rock type cannot be determined from the image alone

Limestone

Calcareous sedimentary rock (CaCO3)

Tumbled milky quartz pebble

Quartz (silicon dioxide, SiO₂), cryptocrystalline to microcrystalline variety

Milky quartz

Quartz (silicon dioxide, SiO₂)

Fossilized sea urchin

Echinoid test, likely a regular sea urchin; calcite (CaCO₃)

Ferruginous Sandstone (Ironstone)

Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)

Rounded quartz-rich pebble

Massive quartz (silicon dioxide, SiO₂), possibly milky quartz or quartzite

Blue quartz (likely tumbled dyed or coated quartz)

Quartz, silicon dioxide (SiO₂)

Fossilized echinoid (sea urchin), likely a sand dollar fragment or small regular urchin

Echinodermata; commonly Clypeasteroida or Echinoida, preserved mainly as calcite (CaCO₃)

Weathered iron-rich rock, possibly jasper or ironstone

Likely limonite/goethite-bearing siliceous rock; exact identification requires hardness and streak tests

Green river-worn pebble, likely serpentinite

Serpentinite (serpentine-group minerals; identification is provisional from the photograph)

Mica-rich schist (tentative)

Mica schist, likely muscovite–biotite schist; exact minerals cannot be confirmed from the image

Gneiss

Feldspathic biotite gneiss; a high-grade metamorphic rock composed mainly of quartz, feldspar, and mica

Pale green calcite

Calcite (CaCO₃)

Rough Apatite in Matrix

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

Weathered quartz-rich cobble, likely milky quartz

Quartz (SiO₂), possibly ferruginous milky quartz

Weathered iron-rich stone, possibly limonite-bearing sandstone or laterite

Goethite–hematite/limonite mixture; exact identification requires testing

Quartz crystal cluster

Quartz (silicon dioxide, SiO₂)

Tumbled milky quartz, possibly quartzite

Quartz (SiO₂); the specimen may be a quartz-rich metamorphic rock if its texture is granular

Milky quartz crystal fragment

Quartz, silicon dioxide (SiO₂)

Possibly biotite-rich schist

Mica schist, composed mainly of quartz and mica (often biotite); exact identification is uncertain from the photo.

Polished milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Feldspar

KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8

Black-and-white veined stone, likely marble or calcite-veined metamorphic rock

Probable calcite marble: predominantly recrystallized calcite (CaCO₃) with dark graphite-, mica-, or amphibole-rich minerals

Likely hornblende amphibolite fragment

Amphibolite, chiefly hornblende and plagioclase feldspar