Colour Sable, Sable and white, Tricolour and Blue Merle. Sable: any shade of light gold to rich mahogany or shaded sable. Light straw or cream coloured highly undesirable. Tricolour: predominantly black with rich tan markings about legs and head. A rusty tinge in top coat highly undesirable. Blue Merle: predominantly clear, silvery blue, splashed and marbled with black. Rich tan markings preferred, but absence should not be penalised. Large black markings, slate colour, or rusty tinge either of top or undercoat are highly undesirable. All should carry typical white Collie markings to a greater or lesser degree. Following markings are favourable – white collar, full or part, white shirt, legs and feet, white tail tip. A blaze may be carried on muzzle or skull, or both.