Dates Of Origin: 1950's. Average Weight Range: 6-10 lbs. Temperament Of The Cornish Rex: Enterprising Acrobat. Breed Colors Of The Cornish Rex: All colors and patterns, including pointed, sepia, and mink. History Of The Cornish Rex: In 1950, a farm cat from Cornwall, England, had a litter with one curly-haired male kitten, Kallibunker.