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Credit: © Warren Anatomical Museum, President and Fellows of Harvard College
Now with 50 collections, not including libraries, amassed over more than 350 years, Harvard has some strange these locked away. Some were brought out as part of a recent exhibit called Tangible Things. This avocado-sized rock is both mineral and medical. Rocks like this, that form within the human body, often around foreign objects, are called calculi. In 1871, a doctor removed this enormous calculus from a soldier shot through the sacrum at the Battle of Gettysburg.