This stamp is very faded but the best I can figure is that it is “M & D Const.” It’s on the north side of Hickory Street between South Pennsylvania and Jones (close to Jones). Unfortunately it is undated.

According to OpenCorporates, there is an M & D Construction Company, Inc., based in Dearborn Heights. It was incorporated in 1968. It previously used the name “M & D Concrete Contractors, Inc.” I can also find the Facebook page of M & D Concrete LLC, based in Romulus. I’m not sure whether those are two different businesses. I’m also not confident they have anything to do with this stamp, since this would seem to be outside their likely service area.