Colour in cultured pearls has many causes, namely organic pigments and the water reservoir where the pearl shell is grown (sea water or freshwater) that has different manganese (Mn) concentrations with impact on nacre's colours. The mollusc species is, of course, one of the most important factors in this process, specially the donor specimen that provides the mantle tissue that is inserted in the gonads or mantle (depending on the culturing method) of a productive pearl mollusc for the formation of the cultured pearl sac. In Fiji, the local pearl oyster Pinctada margaritifera typica has mantle tissue cells that secrete unusual earthy coloured nacre (seen in the oysters' mother-of-pearl shell interior), and thus the colours of those cultured pearls are also expected to be coloured in such a way. Fiji has been producing natural color beaded cultured pearls, with ocasional non-bead "keshis", in relatively limited numbers since 1999 when Justin Hunter, a biologist and visionary, started his blue economy project with a pearl farm in his home land in Savusavu, Fiji, promoting sustainable luxury through marine cultured pearls. Photos © J. Hunter Pearls Fiji
#pearls #pearljewelry #luxury #gemology #jewelry
listopad 01, 2020
Colour in cultured pearls has many causes
