Unknown (Likely Sedimentary Or Metamorphic)

Oyster shell fragment

Ostreidae shell; primarily calcite (CaCO₃)

Quartz geode or quartz-bearing rock

Quartz (SiO₂), likely in a chalcedony- or basalt-hosted cavity

Weathered limestone or marble slab

Likely calcite-rich carbonate stone; exact identification is uncertain from the image

Iron-stained quartz

Quartz (SiO₂), colored by iron-oxide/hydroxide staining

Dark metamorphic cobble, likely slate or phyllite

Foliated metamorphic rock, probably carbonaceous slate/phyllite; exact identification requires testing

Small brown rock fragment

Undetermined; possibly weathered iron-stained quartzite or chert

Mixed rock and mineral specimen collection

Varied silicate, carbonate, and oxide minerals; individual identification is not possible from this group photograph

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz-rich sandstone or quartzite pebble

Granular quartz (SiO₂), possibly with minor feldspar or carbonate cement

Likely limestone or marble fragment

Calcite-rich carbonate rock; possibly marble (CaCO₃)

Quartz-rich mica schist (probable)

Mica–quartz schist; mainly quartz (SiO₂) with muscovite/biotite mica and possibly feldspar

Beach Pebble (Quartzite / Sandstone)

Quartz-rich sedimentary or metamorphic rock pebble

Milky quartz

Quartz (silicon dioxide, SiO₂)

Rounded metamorphic pebble, likely mica schist or gneiss

Mica schist/gneiss; commonly quartz, feldspar, and biotite or muscovite mica

Gray foliated metamorphic rock, likely gneiss or schist

Quartz–feldspar–mica metamorphic rock; exact identification requires a fresh surface and testing

Biotite schist with quartz veins

Quartz–mica schist; primarily quartz (SiO₂), biotite mica, and feldspar

Milky quartz with iron staining

Quartz, silicon dioxide (SiO₂)

Felsic Drill Core (likely Gneiss or Granite)

Felsic Metamorphic Rock (Gneissic profile)

Likely weathered sandstone or metasandstone

Quartz-rich sandstone (possibly weakly metamorphosed metasandstone)

Quartz (Milky Variant)

Quartz (Silicon Dioxide, SiO2)

Possible shale or slate fragment

Fine-grained clay-rich rock; possibly slate (low-grade metamorphosed shale)

Likely pyrite-bearing rock

Pyrite (FeS₂), possibly in a quartz- or iron-oxide-rich matrix

Weathered mica-rich schist

Mica schist, likely muscovite–quartz schist

Small rounded pebble, likely quartz-rich river stone

Indeterminate; likely quartz/chert-bearing lithic clast

Quartz vein in foliated metamorphic rock

Likely quartz-bearing schist or gneiss; visible crystal is quartz (SiO₂)

Milky quartz-bearing rock, likely quartzite or silicified limestone

Quartz (SiO₂), possibly in a quartzite or chalcedony-rich matrix

Raw blue-green apatite crystal

Apatite group, likely fluorapatite — Ca₅(PO₄)₃F

Quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly microcrystalline quartz (SiO₂), possibly with feldspar, mica, and iron-oxide impurities

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Quartz-rich pebble (likely milky quartz)

Quartz, SiO₂

Gneiss (with Mica and Quartz)

Gneissic Metamorphic Rock

Metallic sulfide-rich rock, possibly pyrite-bearing schist or marcasite specimen

Likely pyrite (FeS₂) in a foliated host rock; exact identification requires testing

Banded metamorphic rock, likely gneiss or migmatitic gneiss

Quartz–feldspar–mica gneiss; exact identification requires a fresh surface and mineral tests

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)

Sandstone (Arkose)

Arkose Sandstone (SiO2 with KAlSi3O8)

Small dark rock fragment (not identifiable from the image)

Undetermined; no diagnostic mineral features are visible

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

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

Pink Himalayan Salt (Halite)

Halite - NaCl (Sodium Chloride) with trace Iron Oxide and Magnesium

Himalayan Pink Salt

Halite (NaCl) with trace minerals (Iron, Magnesium, Potassium)

Polished chrysocolla cabochon

Chrysocolla, a hydrated copper phyllosilicate; commonly intergrown with quartz, malachite, or other copper minerals

Weathered dark mineral/rock fragment

Indeterminate; possibly iron-rich basalt, slag, or a sulfide-bearing mineral