Page:Popular Science Monthly Volume 4.djvu/472

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of dark-green chlorite, from the size of a walnut to that of a fifty-pound shot, within which were one or more crystals of corundum, sometimes blue and white, and, in few instances, of ruby color. None of them were entirely transparent; none of the geodes had cavities, as is the case in those of quartz formation; yet the prospect in this direction is most promising. The result thus far, however, is most encouraging in the rock-strata itself, which is the proper gangue of the corundum. With the hundred tons the mine has yielded for abrasive purposes, the workmen have taken from the place of their birth—a solid, undisturbed matrix of ripidolite—beautiful specimens of the nine corundum gems known by lapidaries by the prefix "Oriental," because of their superior hardness and brilliancy; and also because those of this character, in lustre and composition, were first brought from the East. These are known by name as Oriental sapphire, ruby, emerald, topaz, asteria, amethyst, chatoyant, girasol, and white or colorless sapphire, this last often used in place of the diamond. The general characteristics of these stones, such as color, lustre, hardness, etc., are, by the first lapidaries of this country and Europe, pronounced as not inferior to those of the best localities of the Old World. One of them was sold to a lapidary of Amsterdam, Holland, for $4,000. Others of much beauty have been cut, and are owned in this country and Europe. In this connection it is of value to note that Count Bournon, during his investigations, made a list and analysis of the associate minerals found, in transitu, with the sapphires of Ceylon. Colonel Jenks has had a similar list and examination made of those found in situ with the gems of his mine. All the minerals found in the Ceylon gem-deposits are found in the North Carolina locality.

There can be no doubt, therefore, that Colonel Jenks has made the discovery, in America, of the most precious gems next to the diamond, where they have been sought for in vain elsewhere, in a matrix of solid rock-formation. We look for further interesting developments at this unique and thus far unparalleled alumina deposit.


AMONG the published list of questions at the civil service examination of the Board of Health of New York last summer I observed this: "What is the composition of pure air?"

  1. Read before the American Public Health Association, in New York, November 13, 1873. It was voted by the Society to publish this paper in their "Transactions," but, through the courtesy of the Secretary, the author is allowed to publish it independently.