An article in the Franklin Democrat recounts the preaching of Orson Pratt; the plates were said to be 6 or 8 inches square, and six or eight inches thick, with each plate being thick "as a pane of glass."
"Mormonism," Franklin Democrat (Pennsylvania) (March 1832), repr. Fredonia Censor (New York) (March 7, 1832)
We of this place were visited on Saturday last by a couple of young men styling themselves Mormonites. They explained their doctrine to a large part of the citizens in the court house that evening. They commenced by reading the first chapter of Paul’s Epistle to the Galatians; also by giving an account of their founder, Joseph Smith, then an inhabitant of the state of New-York, county of Ontario, and town of Manchester. Having repented of his sins, but not attached himself to any party of Christians, owing to the numerous divisions among them, and being in doubt what his duty was, he had recourse prayer. After retiring to bed one night, he was visited by an Angel and directed to proceed to a hill in the neighborhood where he would find a stone box containing a quantity of Gold plates. The plates were six or eight inches square, and as many of them as would make them six or eight inches thick, each as thick as a pane of glass. They were filled with characters which the learned of that state were not able to translate.