Igneous Or Metamorphic

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Small dark mineral or rock fragment

Undetermined; possibly a dark mafic mineral such as biotite or magnetite

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Pyrite

Iron Sulfide (FeS2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky and Ferruginous Quartz

Silicon Dioxide (SiO2)

Rough Citrine Quartz

Citrine (Silicon Dioxide, SiO2 with iron impurities)

Milky Quartz

Silicon Dioxide (SiO2)

Pyrite

Iron Sulfide (FeS2)

Pyrite

Iron Sulfide (FeS2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Mica

Phlogopite or Biotite group (KMg3(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Pyrite

Iron Sulfide (FeS2)

Likely polished/tumbled dark mineral or glassy rock fragment

Indeterminate from image; possibly hornblende, schorl tourmaline, or obsidian

Milky Quartz

Silicon Dioxide (SiO2)

Weathered limestone or calcareous tufa

Calcite-rich carbonate rock, primarily CaCO₃ (often micritic limestone or travertine/tufa)

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz with Iron Staining

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Biotite in Host Matrix

Biotite (K(Mg,Fe)3AlSi3O10(F,OH)2)

Quartz (Druzy) on Matrix

Silicon Dioxide (SiO2)

Fossil shell fragment

Indeterminate molluscan bioclast, likely aragonite or calcite

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Likely dark mineral or rock fragment

Indeterminate from image; possibly a dark silicate mineral such as hornblende, biotite, or basalt

Small metallic mineral fragment

Unidentified metallic sulfide or native-metal fragment

Iron-stained quartz crystal cluster

Quartz (SiO₂), likely iron-oxide-stained; exact variety uncertain

Milky Quartz

Quartz / Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Milky quartz with iron-oxide staining

Quartz, silicon dioxide (SiO₂), with hematite/goethite inclusions

Tumbled yellow-brown quartz, possibly citrine or iron-stained quartz

Quartz (SiO₂), likely iron-bearing or included variety

Quartz-rich translucent fragment

Quartz, silicon dioxide (SiO₂), possibly chalcedony or vein quartz

Quartz-rich breccia or quartz vein fragment

Silica, primarily quartz (SiO₂), with possible chlorite, feldspar, or iron-oxide inclusions

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Vein (Iron-stained)

Silicon Dioxide (SiO2) with limonite/hematite staining

Small pale mineral/rock fragment

Indeterminate; possibly weathered quartz, calcite, or light-colored limestone