It shows how American ingenuity and skill are entering into the mechanic and other arts that diamond cutting has been so admirably developed here that diamonds cut in Amsterdam are sent to New York for re-cutting. Hitherto Amsterdam has monopolized the work of diamond cutting; and the aim there has been to remove in cutting the least possible weight of the gem. The American plan is to cut mathematically, according to recognized laws of light, so as to secure the utmost brilliancy for the finished stone. The greater loss in weight, as compared with the Amsterdam cutting, is thus more than made good by the superior brilliancy of the product. It appears that the average increase of value given to diamonds by the New York cutting is $5,000 for each person employed for twelve months; also, that our dealers are receiving the best Amsterdam-cut gems from abroad to be re-cut here and returned.