I bought him at about 10 weeks as an exchequer. At that age he looked like an exchequer. But at about 15/16 weeks he started to develop Mahogny feathers. Is he a pure bred exchequer? Can exchequers sometimes develop a 3rd colour? If he is a cross, what is he likely to have been crossed with? Here he is as a youngster looking like any other exchequer: And here he is after he developed the mahogany feathering.