Metamorphic Rock (Composed Of Multiple Minerals)

Limestone

Sedimentary rock composed of Calcium Carbonate (CaCO3)

Dalmatian Jasper

Peralkaline Quartz-Feldspar Rock with Arfvedsonite

Schist

Mica Schist (primarily composed of quartz, feldspar, and mica)

Greenstone / Greenschist

Greenschist (composed primarily of Chlorite, Epidote, and Actinolite)

Sandstone (with minor weathering/pitting)

Clastic Sedimentary Rock (composed mostly of SiO2)

Granite

Felsic intrusive igneous rock

Granite / Arkosic Sandstone (Coarse Igneous or Sedimentary Aggregate)

Granite / Quartz-Feldspar Aggregate

Sandstone

Clastic sedimentary rock (primarily SiO2)

Botryoidal Chalcedony (Geode fragment)

Silicon Dioxide (SiO2)

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2)

Granite

Phaneritic Felsic Igneous Rock

Chert / Jasper

Sedimentary Cryptocrystalline Quartz (SiO2)

Mica-rich rock, likely mica schist

Mica schist, composed chiefly of muscovite and/or biotite with quartz and feldspar

Leopard Skin Jasper

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Red-and-green jasper

Jasper, microcrystalline quartz (SiO₂), colored mainly by iron oxides and possibly chlorite/epidote

Siltstone

Siltstone (primarily composed of quartz and clay minerals)

Granite

Phaneritic intrusive igneous rock (approx. 70 percent SiO2)

Quartzite

Quartzite (composed primarily of Quartz, SiO2)

Not a geological specimen

N/A (man-made object)

Turquoise in Matrix

Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O

Granite

Granite (composed primarily of Quartz, Feldspar, and Mica/Amphibole)

River Siltstone Pebble

Siltstone (primarily composed of silica and clay minerals)

Gravel and Sediment Sample

Mixed clastic sediment

Weathered shale or mudstone fragment

Fine-grained clastic sedimentary rock, likely shale or mudstone; exact identification is uncertain from the photo

Granite

Granite (Mainly Quartz, Feldspar, and Mica)

Diorite

Diorite (intermediate intrusive igneous rock)

Quartzite

Quartzite (composed primarily of SiO2)

Quartzite (River Pebble)

Quartzite (composed primarily of Silica, SiO2)

Quartz-rich metamorphic fragment (likely mica schist)

Mica schist, probably muscovite–quartz schist

Sandstone

Clastic Sedimentary Rock

Sandstone (Quartzose Sandstone)

Sandstone (SiO2 with various trace minerals)

Sandstone

Sedimentary Rock (Quartz arenite/Arkose)

Tumbled jasper (likely brecciated or orbicular jasper)

Microcrystalline quartz (SiO₂) with iron-oxide and rock-fragment inclusions

Blue-gray foliated metamorphic rock, likely slate or phyllite

Slate (fine-grained metamorphosed shale), possibly phyllite; mineral proportions cannot be confirmed from the image

Serpentine-rich serpentinite pebble

Serpentinite, composed chiefly of serpentine-group minerals (lizardite, antigorite, chrysotile), commonly with magnetite and minor brucite

Quartz-rich pegmatite (likely feldspar and quartz)

Granitic pegmatite composed mainly of quartz (SiO₂) and feldspars

Unakite

Altered Granite (Granitic Metamorphic Rock)

Pink granite pebble

Granite, composed chiefly of quartz, potassium feldspar, and mica

Pegmatite

Igneous Pegmatite

Gneiss (Granitic Gneiss)

Gneiss

Blue Apatite

Ca5(PO4)3(F,Cl,OH)

Granite / Gneiss Ballast Rock

Granite (Quartzo-feldspathic rock)