Purington Pavers

There are a few brick streets and sidewalks in various parts of Saint Paul. One day I saw these Purington Pavers:

I can't quite remember where they are, and it's probably best if I don't say, because it sounds like they may be somewhat valuable.

They were made in Galesville, Illinois, at the Purington Brickyards. This page explains the process and some of the company's history. According to that site, "The United States Government selected Purington Pavers to pave the streets of the city of Panama when building the Panama Canal. Cities from Chicago, IL to Deadwood, SD ordered the bricks for their streets." 

Saint Paul was one of them.