Agate (Crazy Lace)
Silicon Dioxide (var. Cryptocrystalline Quartz) · Semi-Precious Gemstone / Decorative Stone.
Crystal System
Trigonal (Hexagonal system variant); Microcrystalline/Cryptocrystalline habit, typically banded or massive.
Mineral Group
Silicates (Tectosilicate group, Chalcedony variety).
Chemical Formula
SiO2 with inclusions of Iron (Fe) and Manganese (Mn) as coloring agents.
Formation Process
Hydrothermal deposition where silica-rich fluids fill cavities in host rock, typically volcanic, at relatively low temperatures.
About This Crystal
Tumbled, polished specimen displaying vibrant swirling bands of red, cream, and grey. It is opaque to translucent with a vitreous to waxy luster.
Physical Characteristics
Color: Red, white, grey, beige; Streak: White; Cleavage: None; Fracture: Conchoidal; Specific Gravity: 2.60–2.65; Fluorescence: Often inert but can show dull yellow or green under LWUV.
Optical Properties
Refractive Index: 1.530–1.543; Birefringence: Up to 0.009; No pleochroism; Uniaxial positive (usually aggregate reaction).
Hardness & Durability
Origin Region
Primarily Chihuahua, Mexico; forms within volcanic and sedimentary rock cavities.
Hardness & Durability
Mohs Hardness: 6.5–7; Toughness: Very High (excellent for jewelry); Stability: High, resistant to chemicals except hydrofluoric acid.
Care & Maintenance
Wash with warm soapy water; avoid ultrasonic cleaners if there are surface-reaching fractures; store away from harder gems like diamond or sapphire.
Rarity & Value
Relatively Common; value is determined by the complexity of the banding patterns and color vibrancy; usually inexpensive ($2-$15 for tumbled stones).
Special Characteristics
Displays 'Crazy Lace' patterns consisting of intricate, fortification-like swirling bands and circular 'eyes' or orbicular inclusions.
Lore & History
Known as the 'Laughter Stone' or 'Happy Lace'; traditionally associated with balancing emotional energy and physical stamina in various cultures.