From the Cambridge Dictionary
rounded (adjective): round or curved src
round (adjective): shaped like a ball or circle, or curved src
I've seen both "round shape" and "rounded shape" many times.
Ngram Viewer shows both are common.
Do they mean the same thing? Are they interchangeable for any cases? Is the consideration for formal vs. informal involved?
For example, "round stone" means the shape of the stone is round. In this particular situation, what's the difference between "round shape" and "rounded shape"?
I don't see the difference between google image: rounded stone and google image: round stone