No, it is a brown (chocolate) moggy and nothing more. Brown is not as common as black in moggies, but it doesn't make a domestic cat rare or valuable in terms of money. Shelters are overflowing with moggies of all colours. Brown cats occur more frequently in certain breeds because they are selectively bred to produce that colour, but it can and does occur in ordinary domestic cats, and it doesn't make them "valuable".
Of course the cat is "worth something" in that it is a life to be valued and a personality to be shared - but in financial terms it's worth no more money than any other moggy.
EDIT to add: that purebred cats such as the Havana Brown are only 'worth something' (and I'm getting more irate about that particular phrase by the second) in that they come from generations of health-tested cats with known good temperament going back several generations, are registered and have papers to prove their ancestry for health purposes, are properly socialised, vaccinated, where possible spayed or neutered before being rehomed, have a health guarantee from the breeder and are always taken back by the breeder, for life, if their new home doesn't work out, and are of good type. Not to mention blood typed, DNA tested, tested before every planned mating for FIV/FeLV, stud fees, vet fees, housing costs, stud housing costs, premium food etc. etc. Ensuring this COSTS breeders a LOT of money and they do not make money from selling kittens - it is an expensive hobby. You can't expect to demand premium kitten prices if your cat without any known genetic or temperament history going back generations that has not been spayed as she should have been, for whatever reason, happens to pop out a kitten of slightly less common colour.