This shop is famous for its glazes; the α-ω above is in the architectural sample display room, and they proudly display pictures of other devotional works they have done. At the National Shrine of the Immaculate Conception, in The District, is a crypt chapel roofed by Gustavino vaults1 constructed of this shop's tile.
Second visit (I wrote a little about the first a couple years back); this time with my whole family, to celebrate a cousin's wedding.
But, in short, Detroit is a nifty city, containing plenty of stuff well worth your praying for its preservation, not to mention the people living there.
1: Gustavino vaulting is assembled (unusual for masonry arches) unsuspended and without scaffolding. Instead it is constructed of units interlocking (a similar idea to Bruneleschi's dome) and self-supporting from the base up — something like the way igloos are built.