Thorin in the Blue Mountains

[Inziladun]

To add a bit to what I was thinking earlier, about the Ered Luin lacking precious metals, and about the Dwarves' obsession with them, there's this from Appendix A, ROTK, that after the Battle of Azanulbizar:

Thráin and Thorin with what remained of their following (among whom were Balin and Glóin)....made a home in exile in the east of the Ered Luin beyond the Lune. Of iron were most of the things that they forged in those days, but they prospered after their fashion, and their numbers slowly increased. But, as Thrór had said, the Ring needed gold to breed gold, and of that or any other precious metal they had little or none.

Looks to me as if Thorin was just too poor to be taken seriously as a king in the Ered Luin.