Henley's Twentieth Century Formulas, Recipes and Processes. Various

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СКАЧАТЬ Quality I. 8 3.5 4 Finest quality. II. 8 3.5 6 Beautiful, but refractory. III. 8 6.5 3 Ordinary, readily fusible. IV. 52 26.0 22 First quality. V. 59 30.0 11 Second quality. VI. 63 31.0 6 Third quality.

      The following analyses give further particulars in regard to different kinds of German silver:

For sheet	Copper	Zinc	Nickel	Lead	Iron
(French)	50.0	31.3	18.7	—	—
(French)	50.0	30.0	20.0	—	—
(French)	58.3	25.0	16.7	—	—
Vienna	50.0	25.0	25.0	—	—
Vienna	55.6	22.0	22.0	—	—
Vienna	60.0	20.0	20.0	—	—
Berlin	54.0	28.0	18.0	—	—
Berlin	55.5	29.1	17.5	—	—
English	63.34	17.01	19.13	—	—
English	62.40	22.15	15.05	—	—
English	62.63	26.05	10.85	—	—
English	57.40	25.	13.0	—	3.0
Chinese	26.3	36.8	36.8	—	—
Chinese	43.8	40.6	15.6	—	—
Chinese	45.7	36.9	17.9	—	—
Chinese	40.4	25.4	31.6	—	2.6
Castings	48.5	24.3	24.3	2.9	—
Castings	54.5	21.8	21.8	1.9	—
Castings	58.3	19.4	19.4	2.9	—
Castings	57.8	27.1	14.3	0.8	—
Castings	57.	20.0	20.0	3.0	—

      In some kinds of German silver are found varying quantities of iron, manganese, tin, and very frequently lead, added for the purpose of changing the properties of the alloy or cheapening the cost of production. But all these metals have a detrimental rather than a beneficial effect upon the general character of the alloy, and especially lessen its power of resistance to the action of dilute acids, one of its most valuable properties. Lead makes it more fusible; tin acts somewhat as in bronze, making it denser and more resonant, and enabling it to take a higher polish. With iron or manganese the alloy is whiter, but it becomes at the same time more refractory and its tendency toward brittleness is increased.

      Substitutes For German Silver.

      There are many formulas СКАЧАТЬ