According to John Sorenson, processing ore gets almost no attention in the Book of Mormon. Only a single time are we unmistakably told of smelting. According to the Jaredite account, King Shule "did molten out of the hill, and made swords" (Ether 7:9). The text is puzzling because refining could have consisted of as simple a process as heating a piece of rich ore and pounding it. Certainly the Jaredite king who had his "fine gold . . . refined " within the confines of a "prison" (Ether 10:7) would not have been hauling bulky ore to such a place for smelting, although it might have made sense to have workers treat small amounts of less-than-fine gold in order to improve its quality. In short, we remain largely ignorant about the technical procedures employed by the Book of Mormon craftsmen. It sounds as if they were within the modest range of skill common in later Mesoamerica. [John L. Sorenson, An Ancient American Setting for the Book of Mormon, p. 282]
“He Did Obtain All His Fine Work Yea Even His Fine Gold He Did Cause to Be Refined”
According to Hugh Nibley, the book of Ether relates the permanent confinement of kings with the institution of forced labor in prisons. Riplakish "did obtain all his fine work, yea, even his fine gold he did cause to be refined in prison; and all manner of fine workmanship he did cause to be wrought in prison" (Ether 10:7) Work in prison, we are told, was the alternative to paying ruinous taxes (Ether (10:6).
Much the same system was used by the Assyrians from the beginning: Tiglath Pileser III tells how, "I laid tribute and taxes upon them; . . . [their horses, their mules,] their camels, their cattle and their sheep (and) workmen without number I carried away . . . All the skilled artisans I shrewdly used to best advantage. Feudal dues, forced labor, and overseers I imposed upon the land of Nairi." "The kings, their rulers, I brought in submission to my feet and imposed taskwork." (The reader should note the combination of dues and forced labor -- the same as in Ether. Even kings were made to serve, as was the case among the Jaredites) [Hugh Nibley, The World of the Jaredites, p. 207]