Tortoiseshell AKA "Tortie"
Torties are not true tri-color cats, because they do not all contain white. Instead of solid blocks, torties' coats weave the black and red throughout, creating a tapestry of color. A forum member described torties beautifully, "they are cloaked in the lovely colors of Fall." Tortoiseshell cats may also be dilute, with softer versions of the colors. Like the tabby, some torties may also have white accent markings, creating a "tortie with white." They also sometimes have an interesting mix of tortoiseshell, with a bonus of tabby patterning mixed throughout. These cats are referred to as torbies. It should be noted that white plays a very small role in the tortoiseshell pattern - most of the color weaving is done with the red and black components.
Because of the associated genetic factors that creates their color patterns, tri-color cats almost always are females, although occasional males crop up (about one in 3,000) Those rare males are almost always sterile, also for reasons of genetics, so don't expect to gain a fortune by selling your male calico cat.
Here at Jazzpurr we have our own sweet tortoiseshell cat named Millie. Click here to view her Cat spotlight page.