sedimentary
Blue Lace Agate
Silicon Dioxide (SiO2) - Chalcedony / Quartz
Hardness: 6.5-7.0 (Mohs scale); Color: Light blue with white or darker blue banding; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific gravity: 2.58-2.64.
- Hardness
- 6
- Color
- Light blue with white or darker blue banding
- Luster
- Vitreous to waxy
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Physical properties
Hardness: 6.5-7.0 (Mohs scale); Color: Light blue with white or darker blue banding; Luster: Vitreous to waxy; Crystal structure: Trigonal/Microcrystalline; Cleavage: None; Specific gravity: 2.58-2.64.
Formation & geological history
Formed through the deposition of silica-rich groundwater in cavities of volcanic or sedimentary rocks, often in layers over thousands of years. Usually associated with Cenozoic volcanic activity.
Uses & applications
Primarily used in jewelry (cabochons, beads), decorative carvings, and as a collector's gemstone for its aesthetic banding.
Geological facts
First discovered in Namibia by George Swanson in the 1960s. It is a variety of chalcedony characterized by its delicate, lace-like patterns and soft blue hue.
Field identification & locations
Identify by its distinct concentric or wavy banding and translucent appearance. Found commonly in Namibia, South Africa, and parts of the United States and Brazil.
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