This is an authentic VAN CLEEF & ARPELS 18K White Gold Chalcedony Mother of Pearl 15 Motifs Guilloche Magic Alhambra Transformable Long Necklace. The necklace is crafted of 18 karat white gold and features 5 Guilloche Alhambra motifs alternating between six chalcedony and four mother of pearl Alhambra motifs. This piece can be worn as a long necklace or transformed into a shorter necklace with a matching bracelet.