All rocks & minerals

Ironstone concretion

Iron-oxide-cemented sediment, commonly goethite (FeO(OH)) and/or hematite (Fe₂O₃)

Ironstone (limonite/goethite-rich rock)

Limonite, a mixture of hydrated iron oxides, commonly including goethite (α-FeO(OH))

Fossilized belemnite rostrum (likely)

Belemnitida, a fossil cephalopod guard; exact genus cannot be determined from the image

Likely mica-bearing metamorphic rock (possibly schist)

Mica schist, composed mainly of quartz and mica (muscovite and/or biotite); identification is approximate from the image

Likely mica schist

Mica-rich schist, probably muscovite–quartz schist

Weathered greenstone (probable)

Chlorite–actinolite–epidote-rich metamorphosed mafic rock; exact identification requires testing

Weathered iron-stained rock fragment

Uncertain from the image; likely an iron-oxide-stained, quartz- and feldspar-bearing rock

Iron-stained quartz-rich rock (likely weathered quartzite)

Quartzite, composed chiefly of quartz (SiO₂), with iron-oxide staining

Iron-oxide-stained rock, possibly hematite-rich ironstone

Likely ironstone with hematite/goethite (Fe₂O₃/FeO(OH)); exact identification needs testing

Iron-stained, veined metamorphic rock (likely gneiss or schist)

Quartz–feldspar-rich gneiss/schist; exact identification is not possible from the photograph alone

Ironstone concretion

Iron-oxide-rich sedimentary concretion, likely dominated by goethite and/or hematite

Iron-oxide-rich rock (likely limonite/goethite)

Goethite, α-FeO(OH), possibly mixed with limonite and other iron oxides

Porous volcanic rock, likely scoria

Scoria (vesicular basaltic to andesitic volcanic rock)

Mica-rich schist (likely mica schist)

Mica schist, composed chiefly of muscovite and/or biotite mica with quartz; exact minerals require testing

Iron-oxide-stained rock, possibly limonite-rich laterite

Limonite (hydrated iron oxides, commonly goethite); exact host rock cannot be determined from the image

Small tumbled quartz pebble

Quartz, SiO₂

Small polished translucent stone, possibly chalcedony or quartz

Undetermined; likely microcrystalline silica (SiO₂), such as chalcedony

Polished orange-and-white agate slice

Banded chalcedony, microcrystalline quartz (SiO₂)

Likely fossilized tooth fragment

Indeterminate vertebrate tooth; species cannot be identified from the image

Tumbled sea glass or pale-green quartz pebble

Indeterminate from image; possibly quartz (SiO₂), but the smooth translucent piece may be man-made glass

Tumbled rose quartz

Quartz (SiO₂), pink variety

Fossiliferous limestone

Bioclastic limestone, composed chiefly of calcite (CaCO₃) and fossil fragments

Reddish granite (likely weathered granite)

Granite, a quartz–feldspar–mica plutonic rock

Fossil-bearing sedimentary rock, likely with a fossil shell or ammonite cross-section

Fossiliferous limestone or calcareous mudstone; fossil identity is uncertain from the image

Fossil-bearing limestone with a probable fossil shell

Fossiliferous limestone; the visible fossil may be a gastropod or other shelly fossil, but the image is not diagnostic enough for species identification.

Rounded metamorphic rock (likely gneiss or schist)

Foliated quartz–feldspar–mica rock; precise identification requires closer examination

Fossiliferous limestone

Bioclastic limestone, predominantly calcite (CaCO₃)

Weathered, foliated metamorphic rock (likely gneiss)

Quartz–feldspar–mica gneiss; exact identification requires closer examination

Weathered, foliated metamorphic rock (likely schist or phyllite)

Probably mica-rich schist or phyllite; exact identification requires close examination of its grains and foliation

Quartz-rich mica schist (tentative)

Quartz–muscovite/biotite schist; exact identification requires closer examination

Mica-rich schist (likely biotite schist)

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

Native copper (likely a small copper nugget)

Copper, Cu; native-element mineral

Red sandstone

Quartz-rich sandstone, likely iron-oxide-cemented arenite

Mica-rich schist (probable)

Mica schist, likely muscovite–chlorite schist; exact minerals cannot be confirmed from the image

Tumbled rose quartz

Quartz (SiO₂), pink variety commonly called rose quartz

Polished red stone, possibly dyed agate or jasper

Unidentified silica-rich material; potentially chalcedony (SiO₂)

Chert (Brown Jasper)

Microcrystalline Quartz (SiO2)

Mica-rich pegmatite (likely muscovite with quartz and feldspar)

Granitic pegmatite; chiefly muscovite mica, quartz (SiO₂), and feldspar

Amber (fossil resin)

Fossilized plant resin; organic material, not a mineral

Likely native copper

Native copper (Cu)

Quartz–feldspar–mica rock, possibly pegmatite

Coarse-grained granitic rock (compositionally granitic pegmatite); exact identification requires closer examination

Milky quartz (rough quartz)

Quartz, silicon dioxide (SiO₂)