'Lopin' -billet of iron and steel bars

Top: Star Left: Double 81 Bernard Middle: Extra-Fine Crolle Right: Washington The Damascus and Twist barrels of most U.S. gunmakers were finished in a black and white pattern; BLACK BEING THE IRON AND WHITE, THE STEEL. "Colored Damascus" was finished in shades ranging from olive to light brown to dark brown. From Greener: "On the Staining of Barrels. There exists innumberable recipes, and in fact almost every maker has his own method. The first I have found to answer uncommonly well, and which it would be a difficult matter to excel. It consists of the following ingredients:- 1 oz. Muriate Tincture of Steel, 1 oz. Sp. Wine, ½ oz. Muriate of Mercury, ¼ oz. Stong Nitric Acid, 1/8 oz. Blue Stone, 1 quart Water. These are well mixed, and allowed to stand a month to amalgamate. After the oil or grease has been removed from the barrels by lime, the mixture is laid with a sponge, every two hours, and scratched off with a steel-wire bruch every morning, until the barrels are dark enough; and then the acid is destroyed by pouring on the barrels boiling water, and continuing to rub them until nearly cool."