Thumb piano, also known as Kalimba, Sanza or Mbira is very typical for Southern African music in such regions, like Zimbabve, South Africa and another countries.
This is made from wood, where is a resonator and metal parts produced a fascinating tones. I must say, that Mbira is tuned to the relative intervals, not to the absolute pitch. Maybe It can be possible to tune it to the pentatonic scale.
Here is the sound: