The Ainu is one of the minorities of Japan, living in the northern part of Japan. Now they are principally living in Hokkaido, but also Sakhalin, and Kuril Islands.
The picture above shows one of Ainu's musical instruments named tonkori. It is a plucked string instrument. The characteristic of this instrument is that players use only notes of open strings. Generally, tonkori has 5 chords. It means you have only 5 notes. It merely has 3 or 6 chords according to the region.
The tonkori is made of ezo spruce or Japanese bigleaf magnolia, and it is about 1m long. Its chords are of animal tendon or of natural fiber.
Ainu people consider it as a human body as is often the case that they consider their tools in this way. Especially, they put a natural stone into the small hole at the center of the instrument where is considered as the navel.
The practice of tonkori or its oral transmission seems to be lost. However, now some musicians coming from Hokkaido use this instrument for their works.
OKI is musician using Tonkori, and sings in Ainu language.
Here, you have tonkori solo played by K. D. earth, musical unit of two brothers from Hokkaido. This music is named Chikyū misaki, in an album entitled EARTH.