Manufacturer and builder 7, 1878
Try the following: 6 parts of niter, 3 of alum, 3 of sulphate of zinc, and 3 of common salt. Mix a part of these with a small quantity of water, and put it upon the articles to he colored; then place them upon an iron plate over a clear fire, so as to obtain a black heat; then they are suddenly plunged into water. This is the most favored method among jewellers for improving a defective color in plated or gilded articles.
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