Mediaeval English gold nobles, but not our King Richard….
Unfortunately this link does not concern itself with Richard III, but it is very interesting anyway. It seems that such coins of the first usurping Lancastrian, Henry IV, are rarer than those of the unfortunate Richard whose throne and life he took. Sound familiar? Except, of course, that in the case of Richard III, just about everything is rarer than Henry VII. And more desirable.