Sedimentary (Chemically Precipitated)

Jasper

Silicon dioxide (Microcrystalline quartz, SiO2 with iron oxide impurities)

Ironstone concretion (likely limonite/goethite-rich)

Iron-oxide/hydroxide-cemented sediment, chiefly goethite (α-FeO(OH)) and limonite; exact identification requires testing

Banded Iron Formation (BIF)

Banded Iron Formation (Magnetite-Hematite-Chert)

Blue Apatite

Calcium phosphate fluoride, Ca5(PO4)3(F,Cl,OH)

Quartz Sand Grain

Silicon dioxide (SiO2)

Honey calcite (yellow calcite)

Calcite, calcium carbonate (CaCO₃)

Banded sedimentary concretion

Likely a carbonate (calcite-rich) concretion with concentric mineral bands; exact composition cannot be confirmed from the image

Ferruginous Sandstone

Arenite with Iron-Oxide Cement (SiO2 with Fe2O3/FeO(OH))

Banded iron formation (ironstone)

BIF; chiefly hematite/magnetite with chert or jasper (Fe₂O₃/Fe₃O₄ and SiO₂)

Yellow calcite

Calcite (CaCO₃), likely honey or amber calcite

Celadonite in Basalt (Green Earth)

Celadonite (K(Mg,Fe2+)(Fe3+,Al)Si4O10(OH)2)

Iron-rich chert or jasper

Microcrystalline quartz (SiO₂), variably stained by iron oxides/hydroxides

Septarian Nodule (Dragon Stone)

Septarian Concretion (CaCO3 + CaMg(CO3)2 + SiO2)

Ferruginous Breccia

Breccia with Iron-rich (Hematite/Goethite) Matrix

Raw honey calcite

Calcite (calcium carbonate, CaCO₃)

Banded iron formation (iron-rich metamorphic rock)

Banded iron formation (BIF), chiefly hematite/magnetite with chert or quartz (Fe₂O₃/Fe₃O₄ and SiO₂)

Polished orange calcite sphere

Calcite (CaCO₃), likely honey/orange calcite

Banded Chert / Flint

Silicon dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Red Sandstone

Quartzose Sandstone (primarily quartz grains cemented by iron oxides)

Calcite (likely chalky calcite fragment)

Calcite, calcium carbonate (CaCO₃)

Hematite

Iron(III) oxide (Fe2O3)

Flint

SiO2 (Microcrystalline Quartz)

Likely brown ironstone or limonite-rich rock fragment

Ironstone, chiefly iron oxides/hydroxides such as goethite (α-FeO(OH)) and limonite

Chert Nodules in Limestone

Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)

Ferruginous Sandstone (Gozzanous)

SiO2 (Quartz) with FeO(OH) (Goethite) or Fe2O3 (Hematite) coating

Weathered limestone

Limestone, predominantly calcite (CaCO₃)

Wishing Stone / Banded Quartz Vein Pebble

Sedimentary pebble with hydrothermal quartz veins (SiO2)

Limonite (Iron Ore/Bog Iron)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Veined Limestone (Micrite) with Quartz/Calcite Veins

Calcium Carbonate (CaCO3) with Silicate or Carbonate inclusions

Flint Nodule with Chalk Cortex

Chert (Microcrystalline Quartz) SiO2

Fossiliferous Limestone

Biogenic Limestone (CaCO3)

Yellow Ocher (Limonite)

Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O

Selenite (gypsum)

Gypsum, CaSO₄·2H₂O; fibrous variety often called satin spar

Milky quartz vein fragment

Quartz (silicon dioxide, SiO₂), massive or granular variety

Tumbled chalcedony (likely milky quartz)

Microcrystalline quartz, SiO₂; possibly pale agate or quartzite

Quartz (Vein Quartz / Chalcedony)

Silicon dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz pebble

Silicon dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)