This fortunately well-lit stamp is on the south side of Prospect Street between Pennsylvania and Eighth. There are a pair of them, and they appear to be handwritten. I had noticed this one before and found it curious, as X is an uncommon initial to appear in a contractor stamp.

I assumed it was a given name such as Xavier. Instead I have discovered that this is most likely the mark of Xtreme Mason Contractors of Laingsburg. Their slogan is “Xtreme Masonry: Fortified with Hell Bricks!”¹

OK, no it isn’t. Their Web site says they are a 100% women-owned business, which might be a first for the blog, and that they specialize in commercial masonry repair and historic building restoration. They were founded in 2005.

¹ I borrowed this joke from a Zippy the Pinhead comic from, I think, the late 1990s. I wish I could find it again. It involves a discussion of things being promoted as “extreme” and ends with Zippy declaring, “Extreme Oreos! Fortified with hell sugar!”