Two strange rock items were discovered in Phu Can hamlet, An Tho commune, Tuy An district at the end of 1995. Later, it was recognized as an ancient musical instrument with date of 2,500 years and named as rock horn. Rock horn is provided with breath inlet and outlet. Its inside part is characterized by spiral edge hole. Sounds with different pitches are produced when blowing.

Rock Horn is made of basalt rock available in the area. Lithophone and pairs of rock horns diversify the traditional music in Phu Yen.

Lithopone and rock horns are the nation’s precious things and kept in Museum of Phu Yen province.