You might consider yourself to be a music buff, but even if you're into the classics, you probably haven't seen an instrument like this. It's called lithophone, and it's Vietnam's oldest percussion instruments -- not to mention one of the most ancient musical instruments in the world.
Comprised of massive stones of different sizes, the lithophone is played using two mallets, and the music it produces is totally magical. So magical, in fact, that the lithophone was placed on UNESCO's instrument list. Hear how it sounds below.