Messrs. Bailey & Co., the leading Jewelers and Silversmiths of Philadelphia, claim the distinction of having first introduced the use of Silver of the full British standard, say from 925-1000 to 930; the American standard being but 900. They now work no other, a test being made monthly by J. C. Booth, Esq., Chief Assayerof the Mint One advantage of thus raising the standard is, that it successfully secures the trade from importations of Silver from England, for purchasers are assured, by a full gurantee, of receiving Silver as pure as that stamped by the English government. This improvement in the quality of Silver also renders the manufactured articles more beautifully white, susceptible of higher polish, and less liable to oxidation and consequent discoloration.
Source: Philadelphia and Its Manufactures: a Hand-book Exhibiting the Development, Variety, and Statistics of the Manufacturing Industry of Philadelphia in 1857 - Edwin Troxell Freedley - 1858
Bailey & Co. - Philadelphia - 1876
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