Mr. Iskin’s last address was in Montgomery, Pennsylvania where he died at age 82 in April, 1968. In summary, Mr. Iskin’s jewelry talents were employed as early as 1917 and he was a jewelry manufacturer for at least 23 years, from 1930 through 1953. He was based in Philadelphia, with an additional location in New York for a time.
Most of the Iskin jewelry available is gold filled, sterling, or vermeil. Yellow gold was used on the entirety of a piece, with rose gold used as a contrasting accent. A common brooch theme is a floral design, with limited use of glass stones, embellished with any or all of the following: bars or pleats, curlicues, ribbons, and leaves. Some designs are more simple and dainty, while others are more ornate. The brooches range in size from one to four inches in height. He also made link bracelets, earrings, and necklaces. Stone colors seem to cover the rainbow and include topaz, pink, red, lime, green, shades of blue, purple. Pearls were also used.
More rare are rhinestone brooches and hinge bangles (and whatever else there is to discover!). I’ve seen three examples of a framed brooch, constructed similarly like a Coro Duette. The frame has three prongs to which a small brooch and a pair of earrings are attached. Another form has one larger pin and two scatter pins on a three pronged frame. My example is marked “Iskin Pat. App.”, and I’m searching for another example in the hopes that it has a patent number.
Social Security record on Ancestry.com
1930 Census, City of Philadelphia, PA
Draft Registration card (WWI), dated June 5, 1917
New York Times, October 12, 1938
New York Times, December, 28, 1953
Jewelers Circular Keystone, August 1936
Collectors Weekly: Carolyn Davis, Harry Iskin Jewelry — Researching Costume Jewelry: [https://www.costumejewelrycollectors.com/vintage-costume-jewelry-research/designers-manufaturers-and-styles/jewelry-manufacturers/harry-iskin-jewelry/]: 
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