Quartz Crystal Bowl These bowls are made by pulverizing quartz crystal and heating it to form a bowl. A (La) = Tuned to a base of 432Hz Set of 7 Diameters range from 12 inches (30 cm) to 7 inches (17.5 cm) Scales are from C (Do) to B (Si) The seven notes of Do Re Mi Fa So La Si No semitones The sound energy emitted from these is wonderful. You can experience very powerful energy. The scale that resonates with each person is different, and some people may have their past memories awakened, or their emotions stirred. There are various effects. Although new, the item has been opened for inspection and photography. Tuned to A4 (La) = 432Hz. Modern instruments are all tuned to A4 = 440Hz, but before 1939, classical music was tuned to 432Hz. Mozart and Vivaldi composed in 432Hz. 432Hz tuning sounds gentler and more beautiful, and has a healing effect. Nowadays, 432Hz instruments are used to let children listen to the scales in Steiner education, etc. Trial performance videos: Posting URLs and linking externally is prohibited by Mercari guidelines. You may be able to find reference videos by searching for "Mercari Hello" on a famous video site. Quartz 1 Quartz 2 Includes: 2 rubber drumsticks 2 leather-covered sticks 7 rubber rings to place under the bowls 2 carrying bags (holds all 7 bowls) Will be shipped in the original box. Shipping included.