2007: Even today many don't know/understand the difference (s) between synthetic and artificial gemstones. The minute you mention synthetic they will ask if it's glass or plastic; to my surprise even gemologists, jewelers and traders ask the same. I call it momentary autism. They go blank/inert. I think gemological education should be perceived as a life long learning endeavor.
(via The Journal of Gemmology, Vol.VII, No.6, April, 1960) A E Farn writes:
Most gem enthusiasts have at some time or other either attended a gemological exhibition, or proudly shown their own collection of gems to friends and relations—always to be asked the inevitable question, ‘how much are they worth?’ To the keen collector, this is an irritating question, since it indicates clearly where the interest lies and how the average person reacts to such terms as gemstones or jewelry. Seldom does one meet the true appreciation of beauty or rarity, but always the eternal ‘how much?’
Unfortunately certain elements in our society readily apply their criminal psychology to this materialistic interest in valuables so quickly evinced by the more greedy or gullible section of the public. Thus, when a new material came on to the market and displayed tremendous fire and attraction for a price low in comparison to diamond it afforded possibilities which the unscrupulous were not slow to realize. The new material’s trade name of fabulite seemed coined specially for word play—fabulous for the credulous! It was not until some fairly recent occasion that I was asked by a gem dealer, who wanted to satisfy a customer’s enquiry, whether it was intended to simulate diamond and if it was a synthetic stone.
Answering rather quickly without very serious thought, I replied that it certainly was not intended to simulate diamond but doubtless it could be so used. It was not synthetic diamond, since its formula was SrTiO3, strontium titanate, but it could be described as a synthetic stone. Since then I have had second thoughts. I began to wonder if it was correct to describe this product as synthetic, and without going into the various aspects and methods of manufacture of synthetics generally I wondered whether it was correct so to describe strontium titanate.
Being weak on etymology I could only have recourse to what I had been taught, and as far as I could remember a synthetic stone is a stone which has the same chemical composition, refractive indices and specific gravity as its natural counterpart.
If a synthetic ruby be analyzed it would correspond with natural ruby and similarly in the case of sapphire. With synthetic spinel this is not quite the same, as here there is an excess of alumina in the composition and the properties are slightly higher in R.I and S.G than those of natural spinel. It would seem to be hair-splitting, but even synthetic spinel is not a true synthesis of natural spinel. It did not intend to propound this particular case, but it slipped in as a natural sequence.
What I really wanted to focus on is: strontium titanate, is it a synthetic, since so far as is known there is no naturally occurring mineral? Certainly it is an artifact as indeed are all synthetics, whether corundum, spinel, rutile or emerald. The Concise Oxford dictionary gives synthesis as ‘combination, composition, putting together. Chemically: artificial production of compounds from their constituents.’ Jarrold’s dictionary of difficult words gives synthesis as ‘combination of parts into a uniform whole. Synthetic—pertaining to synthesis and adjectivally as artificial.’ Webster’s Compendium carefully states, ‘synthetic gems having similar chemical composition to natural corundum and spinel and which in physical and optical properties approximate to these gems are made in an oxy-coal gas furnace (Verneuil process)’. Anderson’s Gem Testing gives: ‘synthetic stones, manufactured stones which have essentially the same composition, crystal structure and properties as the natural mineral they represent.’
It would seem, therefore, that a consensus of opinion is against terming an artifact of no known natural counterpart as a synthetic from a gemological view. Incidentally, most so called synthetics which have a counterpart in nature are all certainly harder than fabulite, which has a softness too low to admit of normal jewelry usage. It would seem therefore that strontium titanate is in fact an artificial stone and should be so described.
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