The following is an extract from an 1838 letter from Lucy’s neighbor, Sally Parker (a convert), to her relative, Francis Tufts
I lived by his mother, and [she] was one of the finest of women–always helping them that stood in need. She told me the whole story…. The old lady told me this herself with tears in her eyes, and they ran down her cheeks too…. I asked her if she saw the plates. She said no, it was not for her to see them, but she hefted and handled them, and I believed all she said, for I lived by her eight months, and she was one of the best of women. (Investigating the Book of Mormon Witnesses, p.25)
When Joseph first obtained the plates he allowed his mother to handle the Urim and Thummim
Lucy Mack Smith
I trembled so much with fear lest all might be lost again by some small failure in keeping the commandments, that I was under the necessity of leaving the room to conceal my feelings. Joseph saw this and followed me. “Mother,” said he. “Do not be uneasy. All is right. See here,” said he, “I have got the key.”
I knew not what he meant, but took the article in my hands and, examining it with no covering but a silk handkerchief, found that it consisted of two smooth three-cornered diamonds set in glass, and the glasses were set in silver bows connected with each other in much the same way that old-fashioned spectacles are made. He took them again and left me, but did not tell me anything of the record….
That of which I spoke, which Joseph termed a key, was indeed nothing more nor less than a Urim and Thummim by which the angel manifested those things to him that were shown him in vision; by which also he could at any time ascertain the approach of danger, either to himself or the record, and for this cause he kept these things constantly about his person. (History of Joseph Smith, Revised and Enhanced, p. 139, 145)
Joseph showed his mother, Lucy, the breastplate
Lucy Mack Smith
After bringing home the plates, Joseph now commenced work with his father on the farm in order to be as near as possible the treasure that was committed to his care.
Soon after this, he came in from work one afternoon, and after remaining a short time, he put on his greatcoat and left the house. I was engaged at the time in an upper room in preparing some oilcloths for painting. When he returned, he requested me to come downstairs. I told him that I could not leave my work just then, yet upon his urgent request, I finally concluded to go down and see what he wanted, upon which he handed me the breastplate spoken of in his history.
It was wrapped in a thin muslin handkerchief, so thin that I could see the glistening metal and ascertain its proportions without any difficulty.
It was concave on one side and convex on the other, and extended from the neck downwards as far as the center of the stomach of a man of extraordinary size. It had four straps of the same material for the purpose of fastening it to the breast, two of which ran back to go over the shoulders, and the other two were designed to fasten to the hips. They were just the width of two of my fingers (for I measured them), and they had holes in the end of them to be convenient in fastening.
The whole plate was worth at least five hundred dollars. After I had examined it, Joseph placed it in the chest with the Urim and Thummim. (History of Joseph Smith, Revised and Enhanced)
I have myself seen and handled the golden plates; they are about eight inches long, and six wide; some of them are sealed together and are not to be opened, and some of them are loose. They are all connected by a ring which passes through a hole at the end of each plate, and are covered with letters beautifully engraved. I have seen and felt also the Urim and Thummim. They resemble two large bright diamonds set in a bow like a pair of spectacles. My son puts these over his eyes when he reads unknown languages, and they enable him to interpret them in English. I have likewise carried in my hands the sacred breastplate. It is composed of pure gold, and is made to fit the breast very exactly. (in Henry Caswall, The City of the Mormons; or, Three Days at Nauvoo, in 1842, 2nd ed. revised and enlarged, (London: J. G. F. & J. Rivington, 1843), 26)