That's it. The brewer's star decorates a window arch on the Administration Building (1886) of the old Schoenhofen Brewery at 18th & Canalport. At one time the brewery occupied the entire block but now only five of the dozen or so original buildings remain. The magnificent Powerhouse (1902) has been beautifully renovated for office space and work is well along on the Administration Building as well.
Here's a shot of the Administration Building from a few months ago. The star (barely visible) is above the lower level window at the far left of the photo below. A much larger brewer's star can be seen at the top center of the building just below the cornice.
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Here's a shot of the Powerhouse with the Administration Building in the background—a couple of the many architectural treasures of Chicago. It's great seeing them restored at long last.