Is the International Silver Company real silver?

Yes, the International Silver Company produced real silver products. The hallmark "IS," however, refers to the brand and does not indicate purity, as International Silver mass produced silverplated flatware and holloware as well as sterling. In order to determine if the piece is real silver, look for the standard marks that indicate purity — the number 92.5 or 925 and the word “sterling” are indicators of sterling quality.

When an object is described as “silver” or “sterling silver,” it means that it contains 92.5% pure silver (the remaining 7.5% consists of copper and/or other alloys). The purity standard was first established in England and later adopted in the United States. The mark on antique British sterling-silver pieces is the lion passant (a lion walking to the left), which signifies a work is 92.5 percent pure sterling; if it’s not there, it is likely silverplate — or not English.

International Silver was a Connecticut conglomerate formed from 17 companies in 1898. It was once the largest manufacturer of silver and silver-plated products in the world.

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