Japan.
Conch shell, metal. H: 14.25” (36.2 cm), W: 7” (17.8 cm), D: 5.25” (13.3 cm).

A beautiful conch shell converted to a trumpet, used by monks for religious purposes.
Unlike most shell trumpets from other parts of the world which produce only one pitch, the Japanese hora or horagai
can produce three or five different notes. The different pitches are achieved using a bronze or wooden mouthpiece
attached to the apex of the shell's spire.

Ex: Private collection, Orange County, California.