Alma's son Helaman is the next in the line of scriptural custodians. However, more than just the large plates of Nephi were entrusted to Helaman. He also was given charge over the interpreters (v. 21), the Liahona (v. 38), the other Nephite records, the plates of the Book of Ether (v. 21), and probably the sword of Laban (See Mosiah 1:16). These were traditionally handed down together to the next prophet-author in the Book of Mormon.
Essentially the same combination of religious artifacts was available to the Prophet Joseph Smith and was shown to the three witnesses. Although Joseph does not describe the event in the History of the Church, David Whitmer is quoted as follows:
"We not only saw the plates of the Book of Mormon but also the brass plates, the plates of the Book of Ether, the plates containing the records of the wickedness and secret combinations of the people of the world down to the time of their being engraved, and many other plates ... there appeared as it were, a table with many records or plates upon it, besides the plates of the Book of Mormon, also the Sword of Laban, the Directors i.e., the ball which Lehi had-and the Interpreters [Urim and Thummim]. I saw them just as plain as I see this bed (striking the bed beside him with his hand), and I heard the voice of the Lord, as distinctly as I ever heard anything in my life declaring that the records of the plates of the Book of Mormon were translated by the gift and power of God." (1878 interview between Orson Pratt and David Whitmer, recorded in Book of Mormon Compendium, pp. 55-56)