This story is from the book Mysterious Archaeological Sites (available on Amazon.com) by George Mitrovic and takes place in Santa Cruz County, Arizona in 1891:
Workers were excavating a basement for a commercial building and surprisingly, enough dug up a clay coffin. In it were the remains of a nine foot tall human with six toes on each foot.
The coffin was clay and buried eight feet deep. There was a granite case inside of the coffin with carvings depicting a man with six toes, and wearing a bird shaped head gear.