Measles boulder?

Well, no. ;) It's not even a conglomerate, altho it looks like one! It's mostly granite, with the large round things weathering out being pods of more iron-rich rock. "Mafic inclusions", in the jargon. Their composition is basaltic, and it's now thought these could reflect "liquid immiscibility"--like oil and water, the granite magma and the basaltic magma didn't mix, with the basaltic liquid forming large "drops." The boulder itself is a glacial erratic. Sierra Nevada, California, USA, near the Blue Lakes.