Synthetic (Not A Rock Or Mineral)

Granite

Intrusive Igneous Rock

Dark igneous rock, likely basalt or diabase, with a second purplish specimen

Basalt/diabase; exact identification is uncertain from the photograph

Moonstone

Adularia or Orthoclase (KAlSi3O8) or Albite (NaAlSi3O8), specifically with lamellar exsolution of albite and orthoclase.

Polymer Clay (Mock Mineral)

Polyvinyl chloride (PVC) with plasticizers and pigment

Red Sandstone

Arenite (primarily quartz with iron oxide cement)

Geode Nodule Fragment

Quartz / Chalcedony Nodule

Sandstone (Micaceous)

Clastic Sedimentary Rock (primarily SiO2 with Mica)

Wishing Stone (Quartz Vein in Greywacke / Basalt)

Quartz vein in host rock (e.g. Meta-basalt or Greywacke)

Gravel and Sediment Sample

Mixed clastic sediment

Sandstone (with Iron Staining)

Arenite (primarily SiO2 with Fe2O3/FeO(OH) oxides)

Sandstone (Iron-stained)

Arenite with Limonite/Hematite staining

Gravel

Unconsolidated rock fragments / detrital sediment

Angular gray rock fragments

Unidentified fine-grained rock; the image does not show diagnostic features sufficient for a specific identification

Vesicular Basalt (Lava Rock)

Vesicular Basalt

Serpentine

Antigorite, Lizardite, or Chrysotile (Mg3Si2O5(OH)4)

Weathered granite or granitic gneiss

Granite: quartz, feldspar, and mica; possibly gneiss if the dark minerals are banded

Druzy Quartz on Chert/Chalcedony

Silicon Dioxide (SiO2)

Blue quartz (likely dyed or synthetic-treated quartz beads)

Quartz, silicon dioxide (SiO₂)

Quartz Geode

Silicon Dioxide (SiO2)

Tumbled yellow jasper (probable)

Jasper, an opaque microcrystalline variety of quartz; chiefly SiO₂ with iron-oxide inclusions

Greenstone pebble (likely altered basalt or serpentine)

Greenschist-facies mafic rock; commonly chlorite–actinolite–epidote ± serpentine

River Rock with Quartz Vein

Basalt or Andesite with Quartz Veining

Copper-bearing Quartz Vein in Host Rock

Quartz with Malachite/Chrysocolla staining

Gneiss (Metamorphic Pebble)

Gneissic Metamorphic Rock

Quartz Druzy (Geode Fragment)

Silicon Dioxide (SiO2)

Emerald

Beryl (variety Emerald), Be3Al2Si6O18 with Cr and/or V

Milky Quartz with Country Rock contact

Silicon Dioxide (SiO2) in contact with Metamorphic/Igneous rock

Apatite

Apatite group mineral (e.g., Fluorapatite - Ca5(PO4)3F, Chlorapatite - Ca5(PO4)3Cl, Hydroxylapatite - Ca5(PO4)3(OH))

Veined Quartzite / Vein-filled Sedimentary Rock

Siliciclastic rock with iron oxide-filled fractures

Tumbled brecciated jasper (likely ocean or mahogany jasper)

Jasper—microcrystalline quartz/chalcedony, SiO₂, with iron-oxide inclusions

Agate Geode

Silicon Dioxide (SiO2) - Chalcedony variety

Sandstone

Arenite (primarily SiO2)

Vein Quartz in Basalt or Mafic Rock

Silicon Dioxide (Quartz veins in volcanic host rock)

Sandstone

Sandstone (clastic sedimentary rock)

Schist (likely Mica Schist)

Mica Schist

Red Sandstone

Arenite (Iron-rich)

Sandstone

Quartz Sandstone (predominantly)

Sandstone and Conglomerate pebbles

Sedimentary clastic rock

Greenish rough stone, possibly serpentine or soapstone

Indeterminate from the image; possible serpentinite (serpentine-group minerals) or talc-rich soapstone

Basalt with Granite Inclusions (Xenoliths)

Mafic igneous rock (Basalt) with Sialic minerals

Faceted colorless gemstone, likely quartz (rock crystal) or synthetic glass imitation

Quartz: silicon dioxide (SiO₂), trigonal crystal system; exact identity cannot be confirmed visually

Druzy Quartz on Matrix

Silicon Dioxide (SiO2)