Mineral With Metamorphic Or Sedimentary Host

Black Sapphire (Basaltic Blue Sapphire)

Corundum (Al2O3)

Jasper with Epidote Vein

Silicon Dioxide (SiO2) with Calcium Aluminum Iron Silicate (Ca2(Al,Fe)3(SiO4)3(OH))

Quartz Geode

Silicon Dioxide (SiO2)

Chert Pebble with Quartz Vein

Microcrystalline Quartz (SiO2)

Likely quartz-bearing mineral aggregate

Quartz (SiO₂), possibly mixed with mica or feldspar

Small polished or naturally worn stone, possibly quartz-bearing rock

Indeterminate from the blurred image; likely quartz (SiO₂) or a pale feldspar-rich fragment

Siltstone Concretion

Carbonate-cemented Siltstone Concretion

Milky Quartz with inclusions

Silicon Dioxide (SiO2)

Quartz-veined Sandstone

Quartzite-veined Arenite / SiO2 and quartz sand

Quartz with Fuchsite (or Chlorite)

SiO2 (Silicon Dioxide) with K(Al,Cr)2(AlSi3O10)(OH)2 (Fuchsite)

Plume Agate

Silicon Dioxide (SiO2)

Chalcopyrite-bearing metamorphic rock (possibly bornite/chalcopyrite ore)

Likely quartz–sulfide rock containing chalcopyrite (CuFeS₂); identification from the image is tentative

Charoite

Charoite (Hydrated potassium sodium calcium barium strontium silicate hydroxyfluoride)

Quartz Veined Siltstone

Siltstone with Quartz Intrusion (SiO2)

Epidote (Unakite-related)

Epidote (Ca2(Al,Fe)3(SiO4)3(OH))

Quartz-encrusted Matrix

Silicon Dioxide (SiO2) with Ferruginous Sandstone

Likely quartz-rich rock or mineral fragment

Quartz (SiO₂), possibly in a pegmatitic or granitic matrix

Quartz with Mica/Host Rock

Silicon Dioxide (SiO2) with Phyllosilicates

Milky quartz vein rock

Quartz (SiO₂), likely in a quartz-rich host rock with minor iron-stained minerals

Blue Apatite

Apatite group (Ca5(PO4)3(F,Cl,OH))

Blue Sapphire (Tumbled/Polished)

Corundum (Al2O3)

Likely quartz-rich pebble in sandstone

Quartz clast (SiO₂) embedded in fine-grained sandstone; exact identification is uncertain from the image alone

Emerald in Matrix

Beryl (Be3Al2Si6O18) containing Chromium/Vanadium impurities

White Quartz

Silicon Dioxide (SiO2)

Tumbled quartz pebble (probable)

Quartz, silicon dioxide (SiO₂), possibly milky quartz or quartz-rich river stone

Likely milky quartz

Quartz (silicon dioxide, SiO₂)

Prasiolite

Silicon Dioxide (SiO2)

Iron-stained Quartz

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Rose quartz

Quartz (silicon dioxide, SiO₂), pink variety

Bronzite

Enstatite (magnesium iron silicate), (Mg,Fe2+)SiO3

Star Sapphire

Corundum (Al2O3) with Rutile inclusions

Black Tourmaline (Schorl)

Schorl (Sodium iron silicate hydroxide boron silicate); NaFe3Al6(BO3)3Si6O18(OH)4

Quartz Veined Jasper

Microcrystalline quartz (SiO2) with calcium carbonate or quartz veins

Quartz Vein in Sandstone

Sandstone with Hydrothermal Quartz (SiO2)

Quartz geode

Microcrystalline and crystalline quartz, SiO₂, likely with chalcedony and iron-oxide staining

Garnet in Matrix

Almandine/Grossular Garnet in Pegmatite or Schist

Shale

Fissile Siliciclastic Sedimentary Rock

Ironstone Nodules (Iron Concretion)

Siderite or Hematite Concretion

Quartz on Host Rock

Silicon Dioxide (SiO2)

Milky quartz vein fragment

Quartz (SiO₂), likely massive or vein quartz with minor iron-oxide/clay inclusions

Quartz-rich translucent fragment

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

Druzy Quartz on Matrix

Silicon Dioxide (SiO2)