I bought a bunch of duplos from the thrift store and inside there was not Just duplos but also mega bloks. I was able to separate most of them but there are a few that I just cannot tell which is which. They have a logo in the middle of the stack but its a picture rather than a word. I'm trying to find anything online but am having no luck. The logo almost looks like a smiling face or an umbrella with 2 dots on each side.