What is a gray Border Collie like?

Gray is a rare Border Collie color; purebred Borders are commonly black-white, plus blue-white, tan-white, tricolor, lilac, and merle. Merles are mostly gray with local white and black patches from a coat gene mutation, looking more distinctive and priced much higher than black-white.

Some merles are tan, possibly carrying yellow-white genes, also a very rare color.