US1580444A - Metallic alloy - Google Patents

Description

letented Apr. l 3.5326.

STATES PATENT OFFICE.

TEQZi'IXl-E P. SHIELDS, 035 NEW YGRK, N. Y., ASSIGNOR TO SHIELD & MQORE, A FIRM CQNSEQTHTG OI" TEOEAE Ti. SHIELDS AND A. MOORE, OF NEW YORK, N. Y.

METALLIC ALLOY.

Ito Brewing.

To all whom may concern:

tie it known that I THOMAS P. Sinmns a i 1r itizen of the Bolted btetes, residing at New York Git New York have invented certain tion with-several. specific examples but it is 15 to he understood that the invention is not restricted to these specific examples.

In s first example, I employ about 58.3% of fine golo, silver, 13% of zinc and 25.2 2 of copper. This produces an alloy which is relatively low in gold, but possesses the property of not readily tarnishing, and this alloy will be found to have the desired green gold color, and. will have good working properies. lhis alloy is very cheap to produce, and can be readily worked. with ordinary goldsmiths tools, and also can be readily enameled.

In this example, as in several of the other 30 examples, the amount of silver can be great-- end if desired can be omitted ly reduced,

and if it 18 desired, to decrease altogether, the amount silver, crease the amount 0t chromium proportionand an alloy to form a good substitute for old, from which silver is entirely absent, would contain about 8% of chr0- mium as a minimum. I

in another particular example, i0% of w {tine gold, of chromium, 30 of copper, 20% of zinc and no silver are employed. In this alloy it isnoted that the amount of gold is relatively low so that the alloy is cheaply produced, and is very suitable for making up jewelry.

The proportions 7 1 oi. cnromiuni, 2% of tiuc' it is preferable to inthe constituents can Application sacs May 20, 1925. Bass No. 31,671.

be varied substantially, and the following table illustrates in a general Way the amount of variation which csnbe had, While still giving very satisfactory products Percent. Gold 4012060 Copper 24m Zinc 10 to 30 Silver 0 to 15 Chromium i 1 to 10 In making up the alloy, I preferably mix together the chromium, copper and zinc (and silver if it is-to be used) in the proportion in which they are toaexist in the final alloy. These'metals can be mixed together, melted and granulated, to form a. stock alloy, and the desired amount of this is added to the desired amount of fine gold, to give the percentage of gold desired, and again melted and stirred, to give the desired tine product.

The final alloys, as will be noted, do not contain any of the ,metals of the platinum group, which have heretofore been used in alloys of this general class, for the prevention of tarnishing. The metals of this group however are extremely expensive, and l find that the alloys produced in accord ance with the present invention arqisubstan tially free from tendency to tarnish, even in the form of jewelry about 10 tov14 carat.

The final alloy can of course contain smell and somewhat immaterial amounts of other substances, which do not materially alter the properties of the final alloy. Thus, in commercial practice, using metals of commercial qualities, some minor amounts of" impurities may be introduced.

1 claim v 1. An intermediate alloy consisting of 1 to 10 parts of chromium, 24 to ports of eoppcn lO to 30 purts of zinc, together with some silver but not substantially above 15 parts thereof. 4 2. An intermediate alloy consisting esseni ially of 8 to 10 parts of chromium, 24 to *ter together amounting to at least 8% of 50 parts of copper, and 10 to 13 parts of the total alloy. zinc. 4;. A gold alloy consisting essentially of 3. A gold alloy "consisting of 40 to 60% 4:0 to 60% of gold, 8 to 10% of chromium,

efgold, 24110 30% of Copper, to 30% of to of copper, and 10 to 30% o'fzinc. zinc, 1 to 10% ofchmmium, and some silver, In testimony whereof I aflix my signature. but not more than 15% thereof, the two lat- I THOMAS P. SHIELDS.