Mineral, Specifically A Rock Fragment

Polished brecciated jasper

Jasper, an opaque microcrystalline variety of chalcedony (SiO₂), with iron-oxide staining

Jasper (specifically Polychrome or Desert Jasper)

Silicon Dioxide (SiO2) with iron oxide and other mineral impurities

Granite Pebble

Granite (Felsic Plutonic Rock)

Rounded pebble, likely mixed lithology

Lithology uncertain; possibly a fine-grained metamorphic or volcanic rock with a quartz-rich/pink feldspar vein or inclusion

Quartz (specifically Quartzite or Massive Quartz)

Silicon Dioxide (SiO2)

Gneiss (specifically Epidote-Quartz Gneiss)

Gneiss containing Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)) and Quartz (SiO2)

Pink Granite

Phaneritic Felsic Intrusive Igneous Rock

Dragon Vein Agate

Silicon Dioxide (SiO2)

Granite

Granite (composed mainly of Quartz, Alkali Feldspar, and Plagioclase)

Likely rough quartz fragment

Quartz (SiO₂), possibly iron-stained or included quartz

Weathered quartz-bearing rock fragment

Indeterminate; likely quartz-rich granite or silicified host rock with iron-oxide staining

Unidentified weathered mineral/rock fragment

Indeterminate; likely a weathered iron-rich silicate or sulfide-bearing specimen

Small gray rock fragment

Indeterminate fine-grained silicate rock; possibly granite, gneiss, or weathered concrete-like lithic fragment

Likely quartz-bearing rock fragment

Quartz (SiO₂), possibly with calcite or feldspar

Feldspar (specifically Orthoclase)

Potassium Aluminum Silicate (KAlSi3O8)

Vesicular basalt (possibly weathered amygdaloidal basalt)

Basalt; chiefly plagioclase feldspar, pyroxene, and commonly olivine, with weathering minerals filling vesicles

Conglomeratic breccia (polymict volcanic breccia)

Polymict volcaniclastic breccia; clasts likely basaltic/andesitic rock in a dark matrix

Pink Granite (with Potassic Feldspar and Quartz)

Felsic Intrusive Igneous Rock (Granite)

Weathered yellow-brown rock pebble

Undetermined; possibly iron-oxide-stained sandstone or mudstone

Weathered granite fragment

Granite, primarily quartz, feldspar, and mica

Granite (specifically the Ubatuba variety)

Phaneritic Igneous Rock (Granodiorite/Monzogranite)

Marble

Recrystallized Calcite (CaCO3) Rock

N/A (This is a digital image of a bar graph)

Digital Data Visualization (Bar Chart)

Sandstone (Ferruginous)

Arenite with Iron Oxide (Limonite/Hematite) coating

Quartz (Clear / Rock Crystal)

Silicon Dioxide (SiO2)

Yellow Calcite

Calcium Carbonate (CaCO3)

Small white mineral fragment

Likely quartz (SiO₂), possibly calcite (CaCO₃)

Montana Moss Agate

Chalcedony (Silicon Dioxide, SiO2)

Unidentified rough mineral/rock fragment

Indeterminate from image; possibly quartz-rich material or weathered carbonate rock

Greenschist

Greenschist (chlorite-epidote schist)

Quartz (specifically Milky or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Mica (Biotite and Muscovite) in Matrix

Potassium aluminum silicate with iron/magnesium (KAl2(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(F,OH)2)

Basalt

Basalt (composition of plagioclase feldspar and pyroxene)

Quartz (Herkimer Diamond variant)

Silicon Dioxide (SiO2)

Amethyst

SiO2 (Silicon Dioxide with Iron impurities and natural radiation influence)

Small pale mineral fragment

Indeterminate; possibly quartz or calcite

Chalcedony (Agate/Carnelian variant)

Silicon Dioxide (SiO2)

Himalayan Pink Salt

Halite (NaCl) with trace minerals

Petrified Wood

Silicified Wood (SiO2)

Pebble

Lithic fragment / Sedimentary clast

Quartz fragment

Quartz (silicon dioxide, SiO₂)

Rounded quartz pebble

Quartz, SiO₂ (likely milky quartz with iron staining)