by Dr. Laurent E. Cartier, first published in Facette 21 (February 2014) We were presented with samples of a new type of pearl product from French Polynesia by a pearl trader during the 2012 BaselWorld show. These cultured pearls had unusual shapes, came in large sizes (up to 23 mm) and were characterised by

by SSEF, first published in Facette 20 (January 2013) Although pearls, as organic gems, are commonly less stable than polished gemstones, we don’t often see pearls with obvious features of surface damage as a result of unfortunate care. A few months ago, however, we received for testing a very spectacular ca

first published in Facette 22 (February 2016) In 2016, the SSEF received a sapphire of exceptional quality and size for testing (Figure 1). The sapphire of 33 ct was characterised by a saturated blue colour, – poetically also known as royal blue and a highly attractive velvety appearance due to submi