John A. Widtsoe discusses Joseph's seer stone; while acknowledging it was made serviceable by God, does not believe Joseph used it to translate the Book of Mormon.
John A. Widtsoe, Joseph Smith: Seeking after Truth, Prophet of God (Salt Lake City: The Deseret News Press, 1951), 260, 267
Before Joseph received the Urim and Thummim he had a stone, obtained during the digging of a well for Clark Chase. This stone, through the blessing of the Lord, became a seer stone which was used frequently by him in his spiritual work.
The use of the seer stone explains in part the charge against Joseph Smith that he was a "peep stone gazer." All his activities were well-known and performed above board. The use of the seer stone and the Urim and Thummim was well-known to the people of his time and neighbourhood.
The use of stones in sacred work has been frequent: for example, the ball known as the Liahona, the rod of Aaron, and the twelve stones used by Lehi. The brother of Jared used sixteen small stones which gave light in the barges. Aids to human senses are always recognized in ecclesiastical history.
Along with the plates of the Book of Mormon were the Urim and Thummim, "two stones in silver bows," used by Joseph Smith as helps in the translation of the inscription on the plates. When the young man was in a suitable spiritual and mental condition, these instruments made the meaning of the inscriptions clear to the translator's mind.
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Some use was made also of the seer stone and occasional mention was made of it. This was a stone found while the Prophet assisted in digging a well for Clark Chase. By divine power this stone was made serviceable to Joseph Smith in the early part of his ministry. There is no evidence that this stone was used in Joseph's sacred work.