Chank-shell (Tsjanka), the popular name of the shell of several species of Turbinella, a genus of (Prosobranchiate) Gasteropod molluscs, natives of the East Indian seas. These shells (especially T. rapa and T. pyrum) are obtained chiefly on the coasts of the south of India and Ceylon, and form a considerable article of trade to Calcutta. They are much used as ornaments by Hindu women. A chank-shell opening to the right is rare, and is highly prized in Calcutta, so that a price of £50, or even £100, is sometimes paid for one.