In fact, Shubael Cottle was originally in partnership with Lewis Mulford and Seth W. Hale until 1877, when he launched his own company, naming it S. Cottle & Co. All records indicate that he was in business until no later than 1920. Your sterling silver brooch dates ca 1877 - 1920.
The other mark, REIN ZINN 95% simply means Pure Tin 95% and is a notation found on most recently made Pewter-ware of all makes. It indicates the percentage of Tin in the alloy used to make this piece.
They are still in business and are mainly a Retailers operation. Practically all of their wares are made to order by several manufacturers here and abroad. Most are decorative and are semi-accurate reproductions of older antique silver items. Your elegant decorative display pieces are Electroplated and probably date ca 1960s - 1990s.
In this case, C.G. & Co. are the initials of the maker of this Silverplated Tray and were used by CHARLES GREEN & Co., located in London (UK). They were established in 1905 as a continuation of the earlier Charles Green & Son business, also in London. The company is reportedly still in business, but moved to Birmingham in 1982. Based on its style, we believe your electroplated Tray dates ca 1920s - 1940s.
Normally, most Silver Plate on Cutlery is Cromargan or Alpaka, an alloy of 65% Copper, 23% Zinc and 12% Nickel, and the the base material is usually of high-grade Stainless Steel. A designation of "G" indicates that they have been plated with a thicker than normal Silver Coating or Layer, often more than 30 microns. This was usually found on German high-end Flatware & Cutlery. Based on its style, we believe it dates ca 1950s.
As you know, at that time, and in fact until very recently, Precious Metals such as Gold, Platinum or Silver were the "guarantee" of a country's Currency Reserves (similar to the Federal Reserve in the US today), and after almost every war, there were massive nation-wide inventories taken to assess the value of Precious Metals reserves in the country in order to print money that would be internationally recognized and assured, known as the "Gold Standard" Monetary System. Items inventoried in this manner were pucnhed with a "Census" mark or hallmark. These Census marks are now well documented and can help in identifying the approximate age and origin of thusly marked items.
Your item is made of Sterling Silver as noted and probably dates ca 1940s - 1950s. The Number 4811 is probably a Model or Pattern number.
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