Problem:
Calico cats are cats that have 3 fur colors and are always female or males two X chromosomes.
I've seen many cats that will have 2 fur colors (one of them is usually white) and another, third, color which is a darker shade of one of the other colors. As exampled in the pictures below (taken from the internet).
Required:
Question: Are those considered Calico cats?
Does anyone know how to go about this search to explain it.