Diamond cutting, though now carried on here much more extensively than ever before, has not always proved a profitable industry. The price for rough diamonds in the London market is so close, and they are disposed of so soon after their arrival, that unless purchases are made with the greatest possible judgment, the competition of the foreign cutters, who are convenient to the market, cannot be successfully met. For this reason the trade has in many cases been given up here, yet the standard of merit has been so raised that to-day the finest cutting is done iu the United States. A large part of the work done here consists in improving and recutting old stones that have been cut in the East for weight only, or in more modern work that can be improved upon, and these branches are generally profitable. But even with a 10 per cent, duty on cut gems as a protection, it is not likely that we shall soon rival the great foreign cutting centers. Sards, bloodstones, and other cheap agates are often cut to a uniform size for mounting, because it is cheaper to fit the stone to the mounting than the mounting to the stone, and such stones as are from time to time found here are generally cut in this country.
At the time of the publication of the last report the writer had not heard of the occurrence of the shale in theElliott county peridotite, hence the statement then made in regard to it; but important investigations have since been made in that locality. In his remarks on the "Genesis' of the Diamond" (Science, Vol. VIII, p. 345), Prof. Carvill Lewis alluded to the peridotite of Elliott county, Kentucky, and suggested that it is well worth while to examine carefully all localities whose geological composition and history are analogous to those of the South African diamond fields. Mr. J. S. Diller, in the American Journal of Science, August, 188C, refers to Prof. A. II. Crandall's having discovered two dikes of eruptive rock in eastern Kentucky, about 1 miles southwest of Willard. Mr. Diller states that he found by microscopic examination that this rock belongs to the peridotites, and occurred in conjunction with a carbonaceous shale; although the exact contact of the two rocks was not exposed, hardened shale was found near the peridotite under such circumstances that the induration is certainly attributable to the influence of the eruptive mass. But this, he thinks, is not the strongest evidence that the peridotite is eruptive, for the peridotite itself includes many fragments of shale which were picked up on its way to the surface. The contact metamorphism has resulted generally in the development of a micaceous mineral, and the production from the shale of a rock such as has been designated spilosite. And in some notes on the trap dikes of Elliott county by A. B. Crandall and J. S. Diller, published in the report on the geology of Elliott county by the Kentucky Geological Survey, Frankfort, Kentucky, 1887 also iu Science, October 21), 188C it is stated that although there were few exposures and the excavations made were inconsiderable, nevertheless he reached the conclusion that the shales had been distinctly metamor-
