Posted by Boris on April 2, 2013, 2:42 am, in reply to "another view"
The necklace (with matching earrings, obviously) was given to Queen Elizabeth II by King Hussein in 1966 and first worn during a 1984 state visit to Jordan. Field identifies the dark stones as sapphires but they certainly look rather like amethysts in the pics. Note also the bracelet in pic 2 (which features one of QE II's lamentable necklines in a dress).