This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Neighbouring triads spiral.svg thumb right This file uses duodecimal duodecimal digits for the keys The triads on the piano keyboard arranged in circle with key numbers from to Major triads start and end with red keys minor triads with blue keys Major thirds are represented by slightly thicker gray lines Black keys have gray