Mineral, Specifically A Rock Fragment

Pyrite-rich Ore

Pyrite (FeS2) with secondary minerals

Quartz (Small Fragment)

Silicon Dioxide (SiO2)

Blue Topaz

Aluminum Silicate Fluoride Hydroxide - Al2SiO4(F,OH)2

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Unidentified pale stone or mineral specimen

Indeterminate; possibly massive quartz, calcite, or a light-colored feldspathic rock

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Unidentified small brown rock

Undetermined; image does not show enough detail for reliable identification

Small rough mineral/rock fragment

Indeterminate; possibly quartz-bearing rock or weathered feldspar

Gravel / Crushed Stone

Aggregate (mixed mineral rock fragments)

Dinosaur Bone (Gembone)

Petrified Dinosaur Bone (Apatite/Silica replacement)

Emerald in Matrix

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Brecciated Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Reddish-brown rock fragment, possibly iron-stained sandstone

Unidentified iron-oxide-stained rock; sandstone is a tentative visual identification

Likely quartz-rich rock fragment

Quartz (SiO₂), possibly iron-stained or mixed with feldspar

Gneiss (specifically Banded Gneiss)

Gneiss

Clear Quartz Cluster

Silicon Dioxide (SiO2)

Granite

Granite, a coarse-grained felsic intrusive igneous rock composed chiefly of quartz, feldspar, and mica

Reddish-brown, iron-stained rock fragment

Indeterminate; possibly weathered porphyritic volcanic rock

Small weathered stone fragment

Undetermined; possibly a feldspar- or quartz-bearing rock fragment

Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite mica

Quartz-rich stone fragment

Likely quartz (SiO₂), though the image is too dim to identify confidently

Angular gray rock fragments

Unidentified fine-grained rock; the image does not show diagnostic features sufficient for a specific identification

Smoky Quartz on Feldspar (Granite Pegmatite)

Silicon Dioxide (SiO2) with Potassium Aluminum Silicate (KAlSi3O8)

Chert (specifically Flint or Gray Chalcedony)

Microcrystalline Quartz (SiO2)

Small pink mineral fragment

Indeterminate; possibly rose quartz or feldspar

Man-made Jewelry (Metal and Glass/Plastic)

Synthetic Alloy and Amorphous Solid (SiO2/Polymer)

Tumbled brecciated jasper

Silica-rich microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and other mineral inclusions

White Topaz

Aluminum Silicate Fluoride Hydroxide; Al2SiO4(F,OH)2

Hag Stone

Perforated Sedimentary Rock / Flint / Limestone

Dalmatian Jasper

Peralkaline Feldspar Diorite/Rhyolite

Jasper Agate (specifically Brecciated Jasper)

Silicon Dioxide (SiO2) with iron oxide and clay impurities

River Rock

Sedimentary clast

Dalmatian Stone

Aplite (often incorrectly called Dalmatian Jasper)

Uncertain small stone; possibly weathered quartz-bearing rock

Indeterminate from image; candidate materials include quartz-rich pebble or altered silicate rock

Orange Calcite

Calcium Carbonate (CaCO3)

Snowflake Obsidian

Obsidian with Cristobalite inclusions

Granite Pebble

Granite (Plutonic Igneous Rock)

Iron-stained jasper (likely rough jasper)

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored by iron oxides

Chert (specifically Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Small weathered mineral/rock fragment

Unidentified; likely quartz-rich material, possibly quartzite or feldspar-bearing rock

Small pale-green stone, possibly serpentine or quartz

Undetermined from the image; no diagnostic features confirm a specific mineral