This is it. This is what I would strive for if I had the option to do the kitchen back splash in any fashion I could choose. I don't even know if this example is actually vintage, but it sure looks right to me. The white flecked tile are classic mid century.
Tiles and mosaics were a very popular design element in the mid century. They moved beyond the walls of the bathroom and kitchen and became common on every day items, table tops and objets d'art (pssst... that's French for "objects of art", by the way).
According to what I've read, the 1/2-inch square ceramic tile size was seen in homes around about the early Sixties. It's use here in the photo with the 1-inch and other sizes make a mosaic eye candy pattern that's not too repetitive. The pale colors also help it to stay in the background without fighting for too much attention.
Brother Dear had made a tiled trivet in shop class back in those days. It's been in use in the kitchen every day since. I look at it, a little piece of MCM design history, and dream about having more of where these came from... it's light blue and white 1/2-inch ceramic tiles with gold flecks glittering off their surface. What I could do with a couple crate loads of those!