Sedimentary (Chemically Precipitated) Or Metamorphic

Quartzite

Quartzite (primarily SiO2)

Marble

Recrystallized Calcite Rock (CaCO3)

Quartzite

Quartzite (primarily SiO2)

Chert / Flint (Artifact)

Microcrystalline Quartz (SiO2)

Lapis Lazuli

Lazurite-dominated metamorphic rock ((Na,Ca)8(AlSiO4)6(SO4,S,Cl)2)

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (specifically Milky or Clear Quartz)

Silicon Dioxide (SiO2)

White Sapphire

Corundum (Al2O3)

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Quartz pebble

Silicon Dioxide (SiO2)

Shale with Vein Infillings

Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Banded Iron Formation

Banded Iron Formation (BIF)

Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Limonite (Iron-rich Siltstone / Sandstone base)

Hydrous ferric oxide mixture (FeO(OH)·nH2O)

Ferruginous Sandstone

Arenite with Hematite/Limonite cement (SiO2 + Fe2O3)

Chalcedony (Common Opal/Chert variety)

Silicon Dioxide (SiO2)

Likely galena-bearing metamorphic sulfide ore

Galena (PbS), possibly with pyrite and/or sphalerite in a schistose host

Lazulite

Lazulite (MgAl2(PO4)2(OH)2)

Gneiss with Quartz Vein

Metamorphic Gneiss

Quartzite Pebble

Quartzite (SiO2)

Quartzite

Quartzite (mostly SiO2)

Quartzite Cobble (Iron-stained)

Quartzite (SiO2)

Blue Quartzite (Blue Aventurine)

Silicon Dioxide (SiO2) with inclusions of Dumortierite or Magnesio-riebbeckite

Quartzite

Quartzite (SiO2)

Quartzite

Quartzite (primarily SiO2)

Quartzite

Quartzite (Primary mineral: SiO2)

Chert (Flint)

Silicon Dioxide (SiO2)

Limestone

Calcium Carbonate (CaCO3)

Limonite pseudomorph after Pyrite

Goethite/Limonite FeO(OH)·nH2O

Chert (Jasper variety)

Microcrystalline Quartz (SiO2)

Garnet (likely Almandine or a blend)

Garnet group: X3Y2(SiO4)3, where X can be Ca, Mg, Fe2+, Mn2+ and Y can be Al, Fe3+, Cr3+. Given the dark, somewhat reddish-brown appearance in the image, it's likely Almandine (Fe3Al2(SiO4)3) or a mix with other iron-rich garnets.

Tiger Iron

Tiger Iron (Hematite, Red Jasper, and Tiger's Eye)

Travertine

Terrestrial Sedimentary Limestone (CaCO3)

Orange Calcite

Calcium Carbonate (CaCO3)

Yellow Calcite

Calcium Carbonate (CaCO3)

Quartzite Pebble

Metamorphic Quartzite (SiO2)

Banded Sandstone

Arenite (Sandstone with iron oxide banding)

Limestone (River Pebble)

Calcium Carbonate (CaCO3)

Aggregate Concrete

Anthropogenic Conglomerate (Technosol)