Tamara, you must mean the Catherine the Great's choker with the detachable bow. There is some similarity with the style indeed.
The wonderful net catalogue by Sotheby's has vanished from their site but I try with this link to show which necklace I ment: http://today.msnbc.msn.com/id/10097587/ns/today-style/t/million-catherine-great-necklace/ --Previous Message-- : this tiara looks like a choker...and it really : resembles in style choker from the Russian : jewels that was sold few years back...too : bad i do not have a photo to : compare...anyone? : : : : --Previous Message-- : : : Bavarian diamond tiara from dona Maria de : Baviera, imperatriz maź do Brasil. : The press release said it was acquired from : a parisian antique shop - Worn by Tamara : Gontijo for her wedding day in Brasilia on : september 20th 2010 : : : : : :