Paraiba 'Nebula' Necklace. Brazilian Paraiba tourmaline slice, set in 18 karat yellow gold, organically shaped edge accented trim of Brazilian green Paraiba melee and E colored white diamonds. 18 karat gold chain, with an organic shaped gold and diamond toggle clasp. Constructed with a hidden back-pin, the bail is articulated to fold down, can be worn as both a brooch and a necklace. Click here to shop now!