Clayton Brough notes that since the time of the Prophet Joseph Smith up to our own day, a number of General Authorities and members of the Church have often expressed their own beliefs and or opinions as to where the Lost Ten Tribes may be located at the present time. Through much research and a number of recent interviews, these theories have been classified under the following four categories:
(1) The Unknown Planet Theory (sometimes called incorrectly the "North Star Theory"): which proposes that the Lost Ten Tribes were taken away from this earth in a manner similar to that of the City of Enoch, and that they now reside on another planet, orb, sphere, and or near another star somewhere in the universe.
(2) The Hollow Earth (or Concave Theory): which proposes that the Lost Ten Tribes possibly reside in either an unknown concave area like in a volcano, or in a great hollow area, somewhere in the region of the North Pole.
(3) The North Pole Theory: which proposes that the Lost Ten Tribes possibly live in a mysteriously camouflaged area somewhere near or at the North Pole.
(4) The Dispersion Theory: which proposes that the Lost Ten Tribes are today totally scattered among the present nations of the earth, and are only lost as to their identity--not as to their location--and are presently being gathered into the Church through missionary labors.
Concerning these theories, Bruce R. McConkie makes the following comment:
There is something mysterious and fascinating about believing the Ten Tribes are behind an iceberg somewhere in the land of the north, or that they are on some distant planet that will one day join itself with the earth, or that the tribe of Dan is in Denmark, the tribe of Reuben in Russia, and so forth. A common cliche asserts: "If we knew where the Lost Tribes were they would not be lost." True it is that they are lost from the knowledge of the world; they are not seen and recognized as the kingdom they once were; but in general terms, their whereabouts is known. They are scattered in all nations of the earth, primarily in the nations north of the lands of their first inheritance. (Bruce R. McConkie, A New Witness for the Articles of Faith, Deseret Book, 1985, p. 520)
Clayton Brough notes that additional comments and opinions by Elder McConkie on the "return" and "restoration" of the Lost Ten Tribes can be found in The Millennial Messiah: The Second Coming of the Son of Man, Deseret Book 1982, pp. 319-329, and A New Witness for the Articles of Faith, Deseret Book, 1985, pp. 520-521, 529-530, 641-642). [R. Clayton Brough, The Lost Tribes: History, Doctrine, Prophecies, and Theories About Israel's Lost Ten Tribes, pp. 108-109] [See the commentary on 2 Nephi 29:13; 3 Nephi 16:1]