Blue-green cabochon, likely chalcedony or treated glass imitation
Cryptocrystalline quartz (chalcedony/possibly chrysoprase); identification uncertain from image
Category
Browse sedimentary (man made conglomerate) specimens identified by the Rock Identifier community.
Blue-green cabochon, likely chalcedony or treated glass imitation
Cryptocrystalline quartz (chalcedony/possibly chrysoprase); identification uncertain from image
Blue Obsidian
Volcanic Glass (SiO2 with inclusions)
Green glass sphere/marble
Soda-lime glass (primarily SiO2, Na2O, CaO)
Milky quartz (rough fragment)
Quartz, silicon dioxide (SiO₂)
Rock crystal (clear quartz), possibly cloudy quartz
Quartz, silicon dioxide (SiO₂)
Quartz Pebble
Silicon dioxide (SiO2)
Tumbled milky quartz
Quartz (silicon dioxide, SiO₂)
Titanium Amethyst Geode
Silicon Dioxide (SiO2) with Titanium/Metal Vapor Deposition Layer
Quartz pebble
Silicon dioxide (SiO2)
Green Glass (often marketed as 'Obsidian' or 'Green Quartz')
Amorphous Silica (SiO2) with copper or chromium additives
Polymictic conglomerate
Clast-supported conglomerate, typically quartz- and feldspar-rich in a dark matrix
Goldstone beads (likely brown goldstone)
Man-made copper-bearing glass; not a natural mineral. Often sold as “aventurine glass.”
Conglomeratic sandstone / breccia-like gravel rock
Polymictic conglomerate (possibly lithified gravel or concrete-like natural conglomerate)
Goldstone (Red)
Aventurine Glass (SiO2 + Cu)
Ferro-slag (Leland Blue/Slag Glass)
Anthropogenic Vitreous Silica (Industrial Slag)
Puddingstone (conglomerate)
Lithified polymict conglomerate, with rounded to subrounded pebble clasts in a finer matrix
Gravel / Small Pebble
Rock Fragment (Gravel)
Blue Crackle Quartz (Dyed Quarzite)
Silicon Dioxide (SiO2) with artificial dye
Dyed Blue Agate (Dragon Vein Agate)
Silicon Dioxide (SiO2) with artificial cobalt/organic dyes
Diamond
Native Carbon (C)
Dyed Aura Quartz
Silicon Dioxide (SiO2) with metallic coating
Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)
Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)
Conglomerate pebble
Polymictic conglomerate (clast-supported)
Polymictic conglomerate
Lithified polymictic conglomerate; clasts likely quartzite, granite, and volcanic rock in a dark matrix
Granite with Cupules / Bedrock Mortars
Granite (felsic intrusive plutonic rock)
Green sea glass (likely)
Man-made glass, likely soda-lime silicate glass; not a natural mineral or rock
Opalite
Synthetic glass (SiO2 + metal additions)
Raw quartz crystal
Quartz (silicon dioxide, SiO₂), likely milky or included quartz
Conglomerate (puddingstone)
Polymict conglomerate; rounded pebbles and cobbles cemented in a finer matrix
Polymict conglomerate
Clastic conglomerate, likely polymictic and matrix-supported
Blue chalcedony (likely dyed or treated)
Microcrystalline quartz, SiO₂ (chalcedony)
Blue Obsidian (Cullet Glass)
Silicon Dioxide (Amorphous Glass)
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz pebble
Silicon dioxide (SiO2)
Quartz pebble
Silicon dioxide (SiO2)
Quartz pebble
Silicon dioxide (SiO2)
Quartz pebble
Silicon dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Tumbled milky chalcedony (likely common opalite-like quartz)
Chalcedony, microcrystalline SiO₂; possibly pale common opal, hydrated SiO₂·nH₂O
Quartz pebble
Silicon dioxide (SiO2)
Obsidian (likely black volcanic glass)
Obsidian; primarily amorphous volcanic silica glass, approximately SiO₂-rich rhyolitic composition
Carborundum
Silicon Carbide (SiC)