Mineral In A Matrix (Likely Quartz Or Feldspar)

Quartz-rich rock, possibly milky quartz

Quartz (silicon dioxide, SiO₂), possibly with feldspar or mica inclusions

Granite

Granite (Phaneritic intrusive igneous rock)

Blue-green mineral specimen, likely chrysocolla or turquoise

Chrysocolla: hydrated copper phyllosilicate, approximately Cu₂H₂O₅Si; Turquoise: CuAl₆(PO₄)₄(OH)₈·4H₂O

Weathered quartz-rich pebble

Likely altered granite or granitic gneiss; chiefly quartz and feldspar with minor mica/iron oxides

Granite Cobble

Granite

Granite Pebble

Granite

Unidentified rock fragments

Indeterminate; likely a weathered, iron-stained silicate rock

Granite

Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)

Porphyritic Rhyolite

Rhyolite

Porphyritic Igneous Rock / Granite or Rhyolite Porphyry

Porphyritic intrusive/extrusive igneous rock

Feldspar (likely Orthoclase or Plagioclase)

Tectosilicate Feldspar (KAlSi3O8 to (Ca,Na)(Al,Si)4O8)

Porphyritic Rhyolite (Birdseye Rhyolite)

Rhyolite (Porphyritic texture)

Quartz (Milky/Smoky variety on matrix)

Silicon Dioxide (SiO2)

Banded gneiss pebble

Gneiss, commonly quartz–feldspar–mica gneiss

Tumbled quartz-rich stone, possibly blue quartz or granite

Quartz (SiO₂), with probable feldspar and dark accessory minerals

Conglomeratic Sandstone

Clastic Sedimentary Rock

Dalmation Jasper (Dalmation Stone)

Perthitic feldspar-quartz-amphibole rock

Granite

Granite (phaneritic felsic intrusive rock)

Dalmatian Jasper

Peralkaline Quartz Feldspar Porphyry

Dalmatian Stone

Dalmatian Jasper (a misnomer) / Perthitic Feldspar Rock

Weathered granite or granitic gneiss pebble

Granite; mainly quartz (SiO₂), feldspar, and mica, with possible gneissic alteration

Biotite-bearing granite or granitic gneiss

Quartz–feldspar–mica rock; chiefly quartz (SiO₂), feldspars, and biotite mica

Epidote in Quartz

{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH) mixed with SiO2

Amygdaloidal Basalt

Amygdaloidal Basalt (extrusive volcanic rock with secondary mineral infilling)

Polished pink feldspar or quartz pebble (uncertain)

Likely microcline feldspar (KAlSi₃O₈) or quartz (SiO₂), with iron-oxide inclusions

Likely gray granite fragment

Granite, composed mainly of quartz, feldspar, and mica

Granite and Igneous Mix

Phaneritic Felsic to Mafic Intrusive Rocks

Polished/tumbled quartz-rich pegmatite

Quartz–feldspar pegmatite, with iron-oxide staining; chiefly SiO₂ and KAlSi₃O₈–NaAlSi₃O₈

Pink Granite

Granite (Alkali-feldspar granite)

Graphic Granite

Graphic Granite (Pegmatitic Alkaline Granite)

Quartz Crystal Cluster on Matrix

Silicon Dioxide (SiO2)

White Howlite

Howlite (Hydrated calcium borosilicate, Ca2B5SiO9(OH)5)

Basalt with Quartz/Feldspar Vein

Amygdaloidal Basalt with Plutonic intrusion (SiO2/KAlSi3O8)

Weathered granite-like pebble

Granite or granitic gneiss; mainly quartz, feldspar, and mica

Milky Quartz with Chlorite/Mica inclusions

Silicon Dioxide (SiO2) with phyllosilicate inclusions

Lepidolite

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite - Lithium-rich Mica)

Pegmatitic granite, possibly potassium-feldspar-rich

Coarse-grained granite; mainly quartz (SiO₂), potassium feldspar (KAlSi₃O₈), plagioclase, and biotite/hornblende

Quartz in Host Rock

Silicon Dioxide (SiO2) in Rhyolite or Granite matrix

Chert Pebble (Jasper/Quartz variety)

Microcrystalline Quartz (SiO2)

Likely weathered granite or granitic gneiss fragment

Quartz–feldspar–biotite aggregate; possibly foliated granitic gneiss

Pink Granite

Granite (Phaneritic igneous rock rich in Alkali Feldspar and Quartz)

Tumbled pink feldspar-rich granite (likely potassium feldspar)

Granite/pegmatitic feldspar aggregate; chiefly KAlSi₃O₈ with quartz and minor mica or iron oxides