Mineralogical

Granite

Intrusive igneous rock composed mainly of quartz, alkali feldspar, and plagioclase

Gneiss (specifically a granitic gneiss cobble)

Gneiss (high-grade regional metamorphic rock)

Quartzite

Quartzite (SiO2)

Granite

Intrusive Igneous Rock

Serpentinite (likely serpentinized ultramafic rock)

Serpentine-group minerals, chiefly antigorite/lizardite; commonly derived from peridotite

Gneiss

Gneiss

Uncertain polymict breccia or altered volcanic rock

Likely hydrothermally altered volcanic breccia; exact mineral identification requires testing

Mica Schist

Mica Schist (primarily Muscovite or Biotite)

Porphyritic polymictic breccia (likely volcanic breccia)

Volcanic breccia; probable polymictic andesite–dacite breccia with quartz/feldspar clasts

Blue-green raw mineral specimen, likely apatite

Fluorapatite, Ca₅(PO₄)₃F (probable; visual identification only)

Likely polished leopard-skin jasper or brecciated jasper

Jasper, an opaque microcrystalline variety of quartz (SiO₂), with iron-oxide and other mineral inclusions; exact variety cannot be confirmed from the image alone

Onyx (Calcite Onyx / Mexican Onyx)

Calcium Carbonate (CaCO3)

Dendritic Agate (or Dendritic Opal)

SiO2 (for Agate), SiO2·nH2O (for Opal)

Chert (Green River Chert)

Microcrystalline Quartz (SiO2)

Granite

Phaneritic Igneous Rock (Granite)

Granite

Intrusive Phaneritic Felsic Igneous Rock

Polished orbicular granite (likely K2-type granite)

Granite, chiefly quartz, alkali feldspar, plagioclase, and dark amphibole/biotite; possible epidote-rich orbicules

Small rounded pebble

Indeterminate lithic grain; likely weathered sandstone, iron-stained quartz-rich rock, or a concretion

Mica Schist (with Golden/Biotite inclusions)

K(Mg,Fe)3AlSi3O10(F,OH)2 (Biotite), KAl2(AlSi3O10)(F,OH)2 (Muscovite)

Weathered iron-rich rock, possibly basalt or ironstone

Indeterminate; likely Fe-oxide-bearing basaltic rock (commonly magnetite/hematite in a silicate matrix)

Weathered sandstone or siltstone

Clastic sedimentary rock, chiefly quartz and feldspar grains cemented by silica, iron oxides, or carbonate

Sapphire

Corundum (Al2O3)

Granite (Dioritic or Hornblende-rich)

Phaneritic Plutonic Felsic to Intermediate Igneous Rock

Iron-rich weathered stone, possibly hematite-rich ironstone

Hematite/goethite-bearing ironstone; predominantly Fe₂O₃ and FeO(OH)

Rhodonite-bearing metamorphic rock

Manganese-rich metamorphic rock, chiefly rhodonite (MnSiO₃), with quartz and manganese oxides

Weathered granite pebble

Granite, chiefly quartz (SiO₂), feldspar, and mica/amphibole

Weathered iron-rich sandstone or ironstone

Ferruginous sandstone, likely limonite/goethite-cemented quartz arenite

Granite

Felsic intrusive igneous rock

Hypersthene

(Mg,Fe)SiO3 - Enstatite-Ferrosilite series

Chert (specifically Silex or Flint)

Microcrystalline Quartz (SiO2)

Granite

Granite

Schist

Schist (various mineralogical compositions including mica, chlorite, talc, etc.)

Drill Core Sample

Cylindrical Rock Core (Specific mineralogy varies by extraction site)

Green Obsidian Sphere (man-made glass)

Vitreous Silica with Chromium/Iron additives

Ocean Jasper (Orbicular Jasper)

Silica (SiO2) with varied mineral inclusions

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Banded River Rock / Gneiss (highly weathered)

Gneiss

Brick

Fired clay or Ceramic material (no specific mineralogical scientific name as it's a composite)

Gneiss

Gneiss (a type of metamorphic rock)

Desert Rose Fragment (Atypical) / Weathered Chert

Silicon Dioxide (SiO2) or Barium Sulfate (BaSO4) depending on exact mineralogy

Banded Gneiss

Gneiss (Metamorphic rock of variable mineralogy, often quartz-feldspar base)

Prasiolite and Quartz Crystal Cluster

Quartz (SiO2); Prasiolite is a variety of Quartz