Expensive fur is a term used to describe luxurious furs that are highly sought after and expensive. ERMINE, MINK, SABLE, and redsable are all examples of expensive fur. ERMINE is a type of weasel with a white winter coat, MINK is a semi-aquatic mammal with a dark brown fur, SABLE is a species of marten with a dark brown fur, and redsable is a type of SABLE with a reddish-brown fur. All of these types of fur are considered to be luxurious and expensive.