Marhop has a point, and with iron in the water I would be cautious too, since a coated drain sees a lot more wear and cleaning than a faucet. A black faucet with a chrome drain does not look off at all, and it is the safer split because the drain is much harder to change later if the finish wears. If you do go black anywhere, stick to a gentle nonabrasive cleaner and skip anything gritty, because harsh cleaners will shorten the life of the coating.