Natural Pearls from Australian <i>Pinctada Maxima</i>

Abstract

Explores the fascinating history of natural pearling in Australian waters and examines the properties that might help distinguish these natural pearls from those that are accidentally produced during the culturing process.

Internal Structures of Known Pinctada Maxima Pearls: Natural Pearls from Wild Marine Mollucks

“…While the identification of most NBC pearls is straightforward, differentiating between some natural and NBC pearls can be challenging because both types are formed almost entirely of nacre and do not contain a shell bead nucleus. The reports on P. maxima pearls from Western Australia (Scarratt et al, 2012) and Lombok, Indonesia (Sturman et al, 2016), are GIA's pioneering studies on pearls of known origin. The samples in both reports were classified as Btype samples since they were collected in situ from mollusks by GIA gemologists after the shells were recovered, and the information for each pearl retrieved is well documented.…”

“…Pearls with internal features that appear to be related to marine organisms are very rare, and only a few have been encountered in the GIA laboratory from the thousands of natural pearls submitted for identification and research. Some examples have been documented in the existing literature (Scarratt et al, 2012;Nilpetploy [nee Somsa-ard], 2015). Even so, the authors were surprised to find four samples in this study group with what are most likely marine organism features.…”

Observations on Pearls Reportedly from the Pinnidae Family (Pen Pearls)

“…Strontium (Sr) levels were on average slightly lower than those usually recorded for saltwater mollusks, but still within the saltwater range. While they do not allow a direct comparison with pen pearl chemical composition, data collected from Pinctada maxima pearls show some similarities when each element is compared (Scarratt et al, 2012). Li and Fe were present in slightly higher concentrations in the pen pearls.…”

Chemical Characteristics of Freshwater and Saltwater Natural and Cultured Pearls from Different Bivalves

“…Few examples of Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) analysis on cultured and natural freshwater and saltwater pearls from different regions can be found in literature [12][13][14][15][16]. However, this method is widely applied on other biogenic calcium carbonates (of freshwater and saltwater) such as molluscs shells and corals, as they are considered to be valuable environmental monitors and archives of paleoclimates [17][18][19][20][21][22].…”