As I remember, the blue ones where the most ordinary (and boring), at least for 3½-inch size. For 5¼-inch, they were mostly black, but I remember some of them in colors too (especially orange or yellow ones, they were beautiful).

E.g: https://c7.alamy.com/comp/2AA9BC4/ajaxnetphoto-2019-worthing...

The same for cameras back in the 60s/70s. Silver was the norm, black was way more desirable. Funnily it's now the opposite.