The company, "Trifari and Trifari" was founded by Gustavo Trifari in 1910. After the stock market crash in 1929, it was designer Alfred Philippe who led the company to greatness. His designs resembled fine jewelry. Later, designs became outrageous and flamboyant.
Trifari changed ownership many times. Some of the owners included Hallmark, Monet, Liz Claiborne and Marvella.One of the signature markings is a crown over the T in Trifari. This marking dates back to the 1940's. The Trifari double ring brooch my sister purchased in Arcola, Chicago has this marking. My precious piece may have been designed in the 1940's. Sorry, my photo doesn't capture the marking on the left side. If you have vintage jewelry marked Trifari you can estimate the date of your piece by its signature. There are over a dozen markings used by Trifari over the years. For more information, go to Researching Costume Jewelry.