Urim and Thummim and Breastplate

During an 1830 trial Oliver Cowdery testified under oath, that “said [Joseph] Smith found with the plates, from which he translated his book, two transparent stones, resembling glass, set in silver bows. That by looking through these, he was able to read in English, the reformed Egyptian characters, which were engraved on the plates."  

The Prophet Joseph Smith's Mother, Lucy Mack Smith recorded the following:

(Replica of the Urim & Thummim courtesy of Steven Reed.)

"On the morning of September 22, after Joseph had returned from the hill, he placed the article [the Nephite interpreters] of which he spoke into my hands, and, upon examination, I found that it consisted of two smooth three-cornered diamonds set in glass, and the glasses were set in silver bows, which were connected with each other in much the same way as old fashioned spectacles. . . . He [Joseph Smith] handed me the breastplate spoken of in his history. It was wrapped in a thin muslin handkerchief, so thin that I could feel 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." (References: Lucy Mack Smith, History of Joseph Smith)