Gold Sheen Obsidian
Volcanic Glass (Amorphous) · Semi-Precious Gemstone / Decorative Stone / Mineral Specimen
Crystal System
Amorphous (no crystal system); typically occurs in massive habits
Mineral Group
Silicates (Volcanic Glass)
Chemical Formula
SiO2 (approx. 70-75%) + MgO, Fe3O4, and various gas inclusions
Formation Process
Igneous; forms when felsic lava extruded from a volcano cools rapidly with minimal crystal growth, trapping microscopic gas bubbles along flow layers.
About This Crystal
An opaque, jet-black volcanic glass carved into a character shape. It exhibits a distinct vitreous luster and a 'golden sheen' effect visible on the face and feet, caused by oriented microscopic gas bubbles.
Physical Characteristics
Color: Jet black with gold-metallic luster; Streak: White; Cleavage: None; Fracture: Conchoidal (shell-like); Specific Gravity: 2.35–2.60; Tenacity: Brittle; Magnetism: None.
Optical Properties
Isotropic (singly refractive); Refractive Index: 1.48–1.51; exhibits Schilller effect (gold chatoyancy) when light reflects off internal gas bubble inclusions.
Hardness & Durability
Origin Region
Primarily Mexico (Jalisco region); also found in the United States and other volcanic regions.
Hardness & Durability
Mohs Hardness: 5.0–5.5; Toughness: Poor (brittle and prone to chipping); Stability: Stable but sensitive to sudden thermal shock.
Care & Maintenance
Clean with warm soapy water and a soft cloth. Avoid ultrasonic cleaners and steam cleaning. Store separately to prevent scratching from harder gems like quartz or beryl.
Rarity & Value
Common; value is determined primarily by the intensity and uniformity of the golden sheen and the quality of the carving. Generally inexpensive.
Special Characteristics
Gold Sheen (iridescence) produced by bubbles of gas or water vapor trapped in the cooling lava, aligned along flow lines to create a chatoyant effect.
Lore & History
Historically used by Mesoamerican cultures for mirrors and ritual objects. Metaphysically associated with the Root Chakra, believed to help with 'shadow work' and protection from negativity.