Note 31 — Chapter I · INTRODUCTORY

But if the later Nahua immigrants also came to regard these chalchihuitl stones with reverence, at the period of their entrance to the Mexican plateau they paid devotion to a mineral of a very different kind. And this it is which helps us to regard their faith as differing entirely from those other faiths which already flourished in the land. The mineral with which their cult was so closely connected was obsidian, a vitreous natural glass found in the upper volcanic strata of Mexico and northern California, which flakes readily from the core by pressure and gains by mere fracture a razor-like edge of considerable penetrative power. The principal quarry of this volcanic glass was the mountain known as the Cerro de las Navajas (“hill of the knives”) near Timapan, and from this centre the itztli, by which name obsidian was known to the Mexicans, was widely distributed by barter over a very considerable area. There would seem to be proof that this mineral, so suitable for the purposes of the nomadic hunter, was anciently known far to the north of Mexico. The observations of Dr. G. M. Dawson31 in British Columbia satisfied him that trading intercourse was engaged in by the coast tribes with those of the interior along the Frazer River Valley and far to the south. From the remotest times embraced in their native traditions, the Bilqula of Dean Inlet have possessed a trade route by way of the Bella Coola River to the Tinné country, along which trail broken implements and chips of obsidian have been found. Many of the routes in British Columbia have also yielded chips and flakes of obsidian, which, the Tinné Indians stated, was obtained from a mountain near the headwaters of the Salmon River (about long. 125° 40′, lat. 52° 40′), formerly resorted to for the purpose of procuring the mineral. The Indian name of this mountain is Bece, which, Dr. Dawson suggested, is the same with the “Mexican” name for knife, itztli, an etymology which may be of Nahuatlac origin. Mr. T. C. Weston, of the Geological Survey, also noted in 1883 the finding of a flake of obsidian in connection with a layer of buffalo bones occurring in alluvium, and evidently of considerable antiquity, near Fort McLeod, Alberta. The nearest source of such a material is the Yellowstone Park region. The coast tribes of British Columbia have been traders for untold generations, exchanging oolactin oil for such material as they could make implements from, and there seems to be no doubt that the Mound-builders of Ohio, Wisconsin, and Kentucky were also acquainted with obsidian, which they could only have obtained by the process of barter. It was thus either to be found in the regions from which the Nahua are thought to have come, or else obtainable through the channels of trade.