The coat may be one of three types: "smooth," "broken," or "rough."
 
Smooth coat: Short, glossy hair.
Undercoat still usually present.

Broken coat: Coarse.
May be some longer whiskering on muzzle and chin.

Rough coat: Longer hair overall, including face, ears, and muzzle.
Very thick, protective double coat.

All coat types should have dense and coarse double coats that are harsh to the touch and weatherproof.

Colours include black, red, bronze, black and tan, chocolate, liver, or even liver and tan and occasionally brindle, but never fully white.
Any other colours, or larger patches of white away from the chest, are indicative of cross-breeding, particularly with the Jack Russell Terrier.
It is traditional for a Patterdale terrier to be of solid colour, with no white markings.
The coat may be one of three types: "smooth," "broken," or "rough."  
Smooth coat: Short, glossy hair. Undercoat still usually present.
Broken coat: Coarse. May be some longer whiskering on muzzle and chin.
Rough coat: Longer hair overall, including face, ears, and muzzle. Very thick, protective double coat.
All coat types should have dense and coarse double coats that are harsh to the touch and weatherproof. 
Colours include black, red, bronze, black and tan, chocolate, liver, or even liver and tan and occasionally brindle, but never fully white. Any other colours, or larger patches of white away from the chest, are indicative of cross-breeding, particularly with the Jack Russell Terrier. It is traditional for a Patterdale terrier to be of solid colour, with no white markings.
Patterdale Terrier