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GIA's most brilliant scientist, Robert Crowningshield, published an article in the Spring 1962 Gems and Gemology, that demonstrates the most complete understanding of any of his colleagues for the process of pearls' nature and cultivation, with the possible exception of Drs Kunz and Cahn, whom he cites in the article's bibliography.

This treatise, about freshwater pearls, is the most complete, yet concise introduction for which the serious student of pearls could hope. If only it had been read and understood, when it was published, by more people in the business of promoting Cultured Pearls, their history would not have been marred,  as it was,  by blunders.  Instead, profound ignorance led the public to unrealistic expectations.  Advertising shrouded in mystery, to the exclusion of facts perceived as unpalatable, eg nacre thickness, color treatments,  and their effects on durability, contributed to disappointment of consumers and retailers alike.

I take the liberty of liberally from this article on its own page, adding the odd underline, and a few footnotes explaining instances of "expert" ignorance.  Salient among these is the oxymoron "tissue nucleated" which was defended, more than 30 years later, by a GIA writer.

 Read important excerpts of  Robert Crowningshield's Insights (published in 1962)

While the history of ocean pearl cultivation is relatively well known, the one of freshwater pearls is not.  Legend has it that General Douglas ("I Shall Return") MacArthur, Commander in Chief of the US Occupation, had Dr A.R. Cahn, aquatic biologist, research Japanese pearl farming so thoroughly that anybody reading his report could do it. For all I know, he succeeded... the problem was that nobody (myself included) ever read it through.  I treasure my copy, which appears to have been mimeographed, but am unequal to the task to disseminating it.

However, while searching Japanese publications, I found the "Chronology of Freshwater Pearling in Japan", which I was able to translate and annotate, and am in the process of extending into the 21st century. 

Readers of pacificpearls.us, kasumipearls.com and pacificpearls.info will be familiar with my attempts at explanation, asides and anecdotes.  I found the records dating from before my time fascinating.

Cross-referencing with contemporary articles, the above and ones of which sensible translation is not yet complete, is revealing.

Statistics, albeit unverified, of the extent this Chronology gives of what I assumed, at the time, was occurring, ie the re-export of China origin pearls as Japanese, are frankly flabbergasting.


For what it's worth, you can read it here.