Smith reports dimensions of the plates to Murdock.
William Smith, Interview with James Murdock, April 18, 1841 “The Mormons and Their Prophet,” Congregational Observer (Hartford and New Haven, Connecticut), July 2 1841, 1, in Dan Vogel, Early Mormon Documents (Salt Lake City, UT: Signature Books, 1996), 1:479
The next day he [Joseph Smith] went alone to the spot, and by digging discovered the plates in a sort of rude stone box. They were eight or ten inches long, less in width, about the thickness of panes of glass; and together, made a pile about five or six inches high. They were in a good state of preservation, had the appearance of gold, and bore inscriptions in strange characters on both sides.