if a diode has color band markings they are on the cathode end

Coronet band

There is no purpose to a coronet band. It is a marking on a horses leg on the very bottom by the fetlock. It is just another marking on a horse just like a star, blaze, face mask, sock, or stocking.

Most diodes have a band (or marking), at one end. The band end is considered the positive end. You can also consider the "band" as a symbol of a gate or blockage. Power flowing from the non-band end to the band end will flow, but power flowing from the band end backwards will not. (That's my method that works for me).

it is a pencil with the word "marking" on the side and it is used for marking