Our beautiful Tibetan (Himalayan) singing bowls with these deep sides are from Orissa. They produce a complex and beautiful harmonic tone helpful in bringing one's mind into a meditative state. The deep sides seem to provide these singing bowls with an especially long sustain. All are old, we believe over 100 years old.
Singing bowls can either be tapped gently with a mallet or rubbed around the rim with a playing stick to produce their tones. It may help to tap the singing bowl gently to begin its vibration.