They were certainly thought to be literal and physical:
Both Lucy Mack Smith and Joseph Knight, Sr., personally remember the time, very late in the night of 21 September and into the morning of the following day, when Joseph and Emma Smith went to retrieve the plates from the Hill Cumorah, and each supplies independent details concerning the events involved.
Joseph Knight, Jr. — “In 1827 [the winter of 1826-1827] he [my father] hired Joseph Smith. Joseph and I worked and slept together. My father said Joseph was the best hand he ever hired. We found him a boy of truth. He was about 21 years of age. I think it was in November  he made known to my father and I that he had seen a vision, that a personage had appeared to him and told him where there was a gold book of ancient date buried, and if he would follow the directions of the angel he could get it. We were told it in secret . . . My father and I believed what he told us. I think we were the first [to believe] after his father’s family [and probably Martin Harris]. . . . At last he got the plates, and rode in my father’s wagon and carried them home.”
The time to receive the plates came at last. When Joseph received them, he came in and said: “Father, I have got the plates.” All believed it was true, father, mother, brothers and sisters. You can tell what a child is. Parents know whether their children are truthful or not. . . . Father knew his child was telling the truth. When the plates were brought in they were wrapped in a tow frock. My father then put them in a pillow case.
I was permitted to lift them as they laid in a pillow case; but not to see them, as it was contrary to the commands he had received. They weighed about sixty pounds according to the best of my judgment.
They were not quite as large as this Bible. Could tell whether they were round or square. Could raise the leaves this way (raising a few leaves of the Bible before him). One could easily tell that they were not stone, hewn out to deceive, or even a block of wood. Being a mixture of gold and copper, they were much heavier than stone, and very much heavier than wood.
William Smith, in an interview with J. W. Peterson:
“I handled them and hefted them while wrapped in a tow frock and judged them to have weighed about sixty pounds. I could tell they were plates of some kind and that they were fastened together by rings running through the back.”
Asked at the end of an 1884 sermon in Deloit, Iowa, about the weight of the plates, William again answered, “As near as I could tell, about sixty pounds.”
 See Lucy’s Book, 376-380; Jessee, “Joseph Knight’s Recollection of Early Mormon History,” 32-39. Joseph Knight, Jr., in his “Autobiography,” also located in the Church Archives, also knew of the events, probably by hearing them from his father. See Backman, Eyewitness Accounts, 72.
 Autobiography of Joseph Knight, Jr., p. 1 (Church Archives), cited in Milton V. Backman, Jr., Eyewitness Accounts of the Restoration (Salt Lake City: Deseret Book, 1986), 72.
 “The Old Soldier’s Testimony,” a sermon preached by William B. Smith in the Saints’ Chapel at Deloit, Iowa, on 8 June 1884, and reported by C. E. Butterworth, in The Saint’s Herald 31 (1884): 643-644. See also William Smith, William Smith on Mormonism: A True Account of the Origin of the Book of Mormon (Lamoni, Iowa: Herald, 1883), 10-11. [See originals.]
 William Smith, William Smith on Mormonism: A True Account of the Origin of the Book of Mormon (Lamoni, Iowa: Herald, 1883), 12. [See original.]
 Smith, “The Old Soldier’s Testimony,” 644. [See original.]
 Anderson, Investigating the Book of Mormon Witnesses, 24. (Check original.)
 “The Old Soldier’s Testimony,” a sermon preached by William B. Smith in the Saints’ Chapel at Deloit, Iowa, on 8 June 1884, and reported by C. E. Butterworth, in The Saint’s Herald 31 (1884): 643-644.
Posted from Carmel, Indiana