Mineral, Possibly Rock Fragment Containing A Mineral

Polished brecciated jasper

Jasper (microcrystalline quartz, SiO₂), likely brecciated and iron-oxide stained

Granite or granitic rock fragment

Granite; primarily quartz (SiO₂), feldspar, and mica

Tumbled jasper (likely brecciated or leopard jasper)

Microcrystalline quartz/chalcedony, SiO₂, with iron-oxide inclusions

Limestone

Calcium Carbonate (CaCO3)

Pumice or vesicular volcanic tuff

Pumice: highly vesicular volcanic glass, chiefly rhyolitic to dacitic; possible tuff: lithified ash and pumice fragments

Weathered volcanic rock, likely vesicular basalt or scoria

Basaltic scoria/vesicular basalt; exact identification requires fresh-surface and mineral tests

Rhyolite (possibly porphyritic and altered)

Volcanic felsic rock; primarily quartz, alkali feldspar, plagioclase, and volcanic glass, with iron-oxide alteration

Green copper-bearing mineral specimen, possibly chrysocolla or malachite

Tentatively chrysocolla, hydrated copper aluminosilicate; may include malachite, Cu₂CO₃(OH)₂

Polished banded agate slab

Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and other mineral bands

Basalt with Granite Inclusions (Xenolith)

Mafic Igneous Rock (Basalt) with Felsic Igneous Inclusion (Granite)

Milky quartz

Quartz (silicon dioxide, SiO₂)

Probable amber fragment

Amber (fossilized plant resin; chiefly amorphous organic resin, commonly dominated by succinite)

Mixed rock and mineral specimen collection

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

Sedimentary Rock (Limestone or Siltstone pebble)

Sedimentary rock fragment

Quartz-rich rock, likely milky quartz vein material

Quartz (SiO₂), possibly iron-stained massive quartz with minor feldspar or mica

Quartz-rich rock, possibly milky quartz

Quartz (silicon dioxide, SiO₂), possibly in a quartzite or weathered host rock

Conglomerate

Conglomerate (SiO2 matrix with varying clasts)

Lapis Lazuli

Lapis Lazuli (Primary mineral: Lazurite (Na,Ca)8(AlSiO4)6(SO4,S,Cl)2)

Serpentinite (likely serpentine-rich rock)

Serpentine-group minerals, chiefly antigorite/lizardite; commonly with magnetite, brucite, or relict olivine

Conglomeratic sandstone or breccia

Lithic arkose / polymictic conglomeratic sandstone

Likely iron-rich slag or weathered ironstone

Hematite–goethite-rich material (Fe₂O₃/FeO(OH)); possibly industrial iron slag

Conglomerate

Clastic sedimentary rock (Puddingstone)

Granite Pebble

Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)

White quartz geode nodule

Quartz (SiO₂), likely a quartz-lined geode or vug in a host rock

Shale

Mudstone/Shale

Quartz-rich pegmatitic rock, possibly altered granite

Quartz–feldspar pegmatite; probable composition of quartz (SiO₂), feldspar, and mica/secondary alteration minerals

Pink-and-green mineral specimen, possibly unakite

Unakite, an epidote–feldspar–quartz rock; identification is uncertain from the photo

Weathered quartz-rich pebble

Likely massive quartz (SiO₂), possibly quartzite or silicified rock

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Limonite with Opal infusion

FeO(OH)·nH2O (Limonite) / SiO2·nH2O (Opal)

Porphyritic Basalt

Porphyritic Basalt (with Plagioclase and Augite phenocrysts)

Red jasper (likely brecciated jasper)

Microcrystalline quartz/chalcedony, SiO₂, colored mainly by iron oxides

Sandstone

Quartz Sandstone (predominantly)

Weathered iron-rich rock, possibly laterite or limonite-bearing sandstone

Laterite/limonite-rich ferruginous material; composition likely hydrated iron oxides such as goethite (FeO(OH))

Banded iron formation (ironstone), possibly jasper–hematite

Banded iron formation; chiefly hematite (Fe₂O₃), magnetite (Fe₃O₄), and silica (microcrystalline quartz/chert)

Sandstone (Quartzose)

Arenite (primarily SiO2)

Sandstone

Arenite (primarily SiO2)

Porphyritic Igneous Rock / Granite or Rhyolite Porphyry

Porphyritic intrusive/extrusive igneous rock

Red Brecciated Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Calcite fragment

Calcite (calcium carbonate, CaCO₃), possibly weathered limestone

Sandstone (Ferruginous)

Ferruginous Sandstone (SiO2 with Fe2O3)

Vesicular Basalt

Vesicular Basalt