Is it a tartan that is officially recognized and accepted by the "powers that be" in your clan? Is it commonly worn by other Pollocks and recognizable as a mark of clan identification?

If the answer to those questions is yes, and you like the tartan, then more power to you!

In my case there is a fashion tartan ("Black MacMillan") that was designed, woven, and marketed as having a connection to my clan, although it is not an officially recognized clan tartan. As a result, I don't wear it.