A Shankha is a conch shell of ritual and religious importance in Hinduism and Buddhism. It is the shell of a large predatory sea snail, Turbinella pyrum, found in the Indian Ocean. In Hindu mythology, the shankha is a sacred emblem of the Hindu preserver god Vishnu.
Conch shells can be used as wind instruments. They are prepared by cutting a hole in the spire of the shell near the apex, and then blowing into the shell as if it were a trumpet, as in blowing horn. Sometimes a mouthpiece is used, but some shell trumpets are blown without one. Pitch is adjusted by moving one's hand in and out of the aperture; the deeper the hand, the lower the note.
Various species of large marine gastropod shells can be turned into "blowing shells", but some of the best-known species used are the sacred chank or shankha Turbinella pyrum, the Triton's trumpet Charonia tritonis, and the queen conch Strombus gigas.