University of Illinois archaeologist Robert Mazrim wasn't looking for anyone who made history or even earned a footnote. He just wanted to understand the average lives of French settlers who lived in the Mississippi River Valley hundreds of years ago.

But a shard of "too-fashionable" pottery stoked his curiosity and led him eventually to claim a thrilling discovery: the site of the home where Pierre Laclede, the founder of St. Louis, likely lived when he first sailed up the Mississippi River from New Orleans.