UNITED STATES. INDIANA.
No further diamond occurrences of any importance have been reported lately within the United States. Two or three small stones have been found in Morgan County, Ind., in cleaning up the sluices of a gold-washing plant recently installed about 29 miles from Indianapolis. These facts were communicated to the writer by the State geologist, Prof. W. S. Blatchley, who also mentions the finding of a few sapphires and rubies in the same association, some of which have been cut into small gems for directors of the gold-washing company. For previous references to gold and various minerals, including corundum, in the glacial gravels of this region, see report of this Bureau for 1902, page 814.
Professor Blatchley states that he had learned of an offer of $1,200 having been made for the "Maxwell" diamond, one of the earlier stones from this vicinity and the best that has been yet obtained in the State, the value being mainly a local one, as the gem value only is a small part of the sum.
As to the source or sources of these diamonds, supposed to be drift diamonds transported by ice from Canada, a letter from Dr. H. M. Ami, of the Canadian Geological Survey, states that no diamonds have yet been found within Dominion territory, although much interest has been awakened by the discussion of the subject in the public press, and many persons have been on the lookout for occurrences.
The new National Transcontinental Railway, from Quebec to Winnipeg and the great wheat region of Manitoba, will traverse much of the country whence the drift diamonds have probably come, and Doctor Ami states that the Government is sending out numerous survey parties for exploration along the route. Some of these may make interesting and even important discoveries.
With regard to diamonds in California, it seems as though the extensive dredging operations now being conducted upon the goldbearing gravels of that State should bring to light many diamonds. though none have as yet been reported. By this process large areas of auriferous gravel are being exploited on a great scale, the. whole deposit down to bed rock being taken out and washed. The process is described in all its aspects and at all the localities in a recent bulletin (No. 36) of the State Mining Bureau of California/' a publication