How is sardonyx formed?
Score: 4.2/5 (41 votes) Bands of sard and white chalcedony are called Sardonyx. Sard forms from the deposition of silica at low temperature from silica-rich waters percolating through cracks and fissures in other rocks. One famous locality for sard is Ratnapura, Sri Lanka.Where is sardonyx found?Sar...