This is a gorgeous piece.  It is in amazing condition.  I do not think this was worn much at all.

The pendant/pin is 32mm north to south and 29mm east to west.  The bale opening is 3mm.   The main stone is a pearl, it is 3mm in diameter.  It is not hallmarked, but has been tested, and verified weighing in at 6.7 grams.  There are no problems.  This item is pre-owned and there will be ordinary and normal use marks. Comes from a clean, smoke-free home. 
 

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