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Pergunta: Existe uma caverna na monte Cumora contendo os registros nefitas?
Question: Is there a cave in the Hill Cumorah containing the Nephite records?
On June 17, 1877, Brigham Young related the following at a conference:
I believe I will take the liberty to tell you of another circumstance that will be as marvelous as anything can be. This is an incident in the life of Oliver Cowdery, but he did not take the liberty of telling such things in meeting as I take. I tell these things to you, and I have a motive for doing so. I want to carry them to the ears of my brethren and sisters, and to the children also, that they may grow to an understanding of some things that seem to be entirely hidden from the human family. Oliver Cowdery went with the Prophet Joseph when he deposited these plates. Joseph did not translate all of the plates; there was a portion of them sealed, which you can learn from the Book of Doctrine and Covenants. When Joseph got the plates, the angel instructed him to carry them back to the hill Cumorah, which he did. Oliver says that when Joseph and Oliver went there, the hill opened, and they walked into a cave, in which there was a large and spacious room. He says he did not think, at the time, whether they had the light of the sun or artificial light; but that it was just as light as day. They laid the plates on a table; it was a large table that stood in the room. Under this table there was a pile of plates as much as two feet high, and there were altogether in this room more plates than probably many wagon loads; they were piled up in the corners and along the walls. The first time they went there the sword of Laban hung upon the wall; but when they went again it had been taken down and laid upon the table across the gold plates; it was unsheathed, and on it was written these words: "This sword will never be sheathed again until the kingdoms of this world become the kingdom of our God and his Christ." 
There are at least ten second hand accounts describing the story of the cave in Cumorah, however, Joseph Smith himself did not record the incident.  As mentioned previously, the Hill Cumorah located in New York state is a drumlin: this means it is a pile of gravel scraped together by an ancient glacier. The geologic unlikelihood of a cave existing within the hill such as the one described suggests that the experience related by the various witnesses was most likely a vision, or a divine transportation to another locale (as with Nephi's experience in 1 Nephi 11:1). John Tvedtnes supports this view:
The story of the cave full of plates inside the Hill Cumorah in New York is often given as evidence that it is, indeed, the hill where Mormon hid the plates. Yorgason quotes one version of the story from Brigham Young and alludes to six others collected by Paul T. Smith. Unfortunately, none of the accounts is firsthand. The New York Hill Cumorah is a moraine laid down anciently by a glacier in motion. It is comprised of gravel and earth. Geologically, it is impossible for the hill to have a cave, and all those who have gone in search of the cave have come back empty-handed. If, therefore, the story attributed to Oliver Cowdery (by others) is true, then the visits to the cave perhaps represent visions, perhaps of some far distant hill, not physical events.
Given that the angel Moroni had retrieved the plates from Joseph several times previously, it is not unreasonable to assume that he was capable of transporting them to a different location than the hill in New York. As Tvedtnes asks, "If they could truly be moved about, why not from Mexico, for example?"
- Brigham Young, "TRYING TO BE SAINTS, etc.," (June 17, 1877) Journal of Discourses 19:38.
- Cameron J. Packer, "Cumorah's Cave," Journal of Book of Mormon Studies 13/1 (2004): 50–57. off-site PDF link wiki
- John A. Tvedtnes, "Review of Little Known Evidences of the Book of Mormon by Brenton G. Yorgason," FARMS Review of Books 2/1 (1990): 258–259. off-site