His color is truly interesting. It reminds me of roaning in horses - by the time a foal sheds the foal coat for the first time, the roaning appears. In horses it is much like Basil - the body color looks roany, but the legs (points) and head are dark. Some roans even have spots like Basil, these are called "corn spots". I am not aware that roaning occurs in cats, but I am nowhere near a color genetics expert.

My own cat Bo started out pure white as a kitten, and as he got older this ears, tail and face mask darkened. Then by the time he was a year old, he got a large flame patch over his body. He has blue eyes, so I figure he has Siamese blood in him.