Are you asking because you have that on an existing house and are trying to match it, or do a repair?
If so, your best resource for figuring out things like this is to contact the builder who built your house. If you don't know who that is, do the legwork, and find out...Most builders (the good ones, anyway) keep records.
Another resource would be to find distributors of stone veneers in your local area, there is a good chance that the materials were sourced from one of them.