Blue-beaded gemstone jewelry, likely lapis lazuli or dyed blue agate
Uncertain from the image; possible lazurite-bearing lapis lazuli (Na₃Ca(Si₃Al₃)O₁₂S) or blue chalcedony (SiO₂)
Category
Browse antropogenic (man made material) specimens identified by the Rock Identifier community.
Blue-beaded gemstone jewelry, likely lapis lazuli or dyed blue agate
Uncertain from the image; possible lazurite-bearing lapis lazuli (Na₃Ca(Si₃Al₃)O₁₂S) or blue chalcedony (SiO₂)
Granodiorite
Granodiorite
Polished blue-green glassy slag or coated mineral fragment
Most likely man-made colored glass/slag; exact composition cannot be determined visually
Diamond
Carbon (C)
Tumbled amber-colored chalcedony or jasper
Microcrystalline quartz (SiO₂), likely iron-stained chalcedony/jasper
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
Banded Sandstone
Arenite with Liesegang banding
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
Chert (Chocolate or Brown Flint)
Chert (SiO2)
Quartzite
Silica (SiO2) quartzite
Diamond (in a jewelry setting)
Diamond (Carbon, C)
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
Diamond
Carbon (C)
Chert (Flint)
Microcrystalline quartz (SiO2)
Banded Calcite (often commercially sold as 'Mexican Onyx' or 'Honey Onyx')
Calcite (Calcium Carbonate, CaCO3)
Chert (variations include Flint/Novaculite)
Chert (formula: SiO2)
Chert (often called Flint for darker varieties)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (and Jasper/Chalcedony mixture)
Microcrystalline Quartz (SiO2)
Coal (Anthracite / Bituminous)
Organic Sedimentary Rock (Carbon-based)
Tree Agate
Chalcedony (SiO2)
Chert (Nodule)
Chert (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (and Flint)
Silicon Dioxide (SiO2)
Sandstone
Arenite
Goldstone
N/A (Synthetic Glass with Copper Inclusions)
Basalt
Basalt
Diorite
Diorite
Diorite
Intermediate plutonic igneous rock
Tumbled purple quartz, likely amethyst or lavender quartz
Quartz (SiO₂), probably iron-colored amethyst; exact variety uncertain from the image
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Pearl
Pearl (Calcium Carbonate with organic conchiolin, CaCO3)
Lapis lazuli and green-blue chalcedony jewelry
Lapis lazuli: lazurite-bearing metamorphic rock, chiefly lazurite (Na₃Ca(Al₃Si₃O₁₂)S) with calcite and pyrite; second stone: likely chrysoprase or green-blue chalcedony (microcrystalline quartz, SiO₂)
Slag Glass (Cullet)
Amorphous Silicon Dioxide (SiO2) with metal oxide colorants
Slag (Anthropogenic Glass/Iron byproduct)
Ferro-silicate Slag
Granite
Phaneritic plutonic rock (SiO2 typically >69%)
Coquina
Biogenic Limestone (Calcite/Aragonite base, CaCO3)
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (Calcium Carbonate, CaCO3)
Faceted Glass (Costume Jewelry)
Amorphous Silicon Dioxide with colorants (Glass)
Diamond
Carbon (C)
Chert
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Tektite
Impactite (Natural Silicate Glass)