Enhancement, Heating & Treating Ruby & Sapphire

A Brief History of Ruby & Sapphire treatments, the City of Chanthaburi and the methods and places in the market.

Ruby & Sapphire, the two different colored gems deriving from the same mineral group, have a long and illustrious history. Their use as talismans, icons and adornments, symbolic of wealth, love, or sovreign and religious powers is woven deeply into our collective and ancient histories.

As could be expected, when money is to be made, even as far back as ancient times, people sought ways to increase the beauty and value of gemstones.

Ruby & Sapphire Heating from Ancient Times until the 19th Century

In one of the first accounts of the world as it was then, Pliny the Elder, venerable statesman, observer and chronicler of Ancient Greece wrote about the treatment and financial gains to be made regarding gemstone treatment1. However, there was no direct reference to ruby or sapphire in Pliny’s chronicles, and it would take until after the Dark Ages for the first codified accounts of the treatment of ruby and sapphire.

The first surviving record referring to sapphire treatment is from the 11th Century written by the central Indian King Bhojaraja2, although it is likely he based his writing on earlier records. Al-Beruni3, a brilliant Arabic scientist, also in the 11th Century, chronicles the use of gold-smelting apparatus, which by definition must be capable of heating up to the melting point of gold (1054 degrees) at a minimum4. Teifschi, added to the narrative in around the year 1240, by chronicling the heat treatment of ruby in Ceylon5.

By the time we reach the 1500’s, the Europeans, in their age of exploration and renaissance, start to chronicle heat treatment referring to the value-add process6, and also to processes that are arguably references to primitive thermal-shock-resistance powder and also reducing-atmosphere clay packs7,8.

Birth of Pre-Modern Heat Treatment in Ruby & Sapphire

By the 1900’s, improvements in refractory technologies had much improved, resulting in insulated ovens that could now reach temperatures much higher than before. In Western Europe, the synthesis of ruby and sapphire was now made possible with the creation of Geneva and Verneuil ruby.

It is thought that these early crystal-scientists and their heirs or apprentices were responsible for clandestinely heating rubies and sapphires in secret from the 1920’s up until the 1960’s. Robert Crowningshield, an early gemologist in the 1960’s, inadvertently chronicled the exhibition of chalky fluorescence in Short Wave Ultra Violet light on Australian sapphire7, which, we now know with the benefit of hindsight, is a classic tell-tale sign of heat-treatment.

Enter the Geuda – Ceylon Raiders

The 1970’s, Chanthaburi, Thailand. Ruby mining was in full swing as a response to Burmese rubies being off the market due to the country’s self-imposed isolation of that period. Across the border in Cambodia, the Indochina wars were spiraling out of control with the then increasingly powerful guerrilla-group Khmer Rouge on the rampage and seek funding via the sales of ruby to the Thais just across the border.

Chanthaburi city, by now a centre of gem cutting and mining, had thousands of people involved in the ruby and sapphire industry. Somewhere in the streets of Chanthaburi fertile petri-dish of know-how and capital. What happened next is unclear.

Tales of street fires changing the color of sapphires, and other local urban myths of sapphires being carelessly left in dopping flames.

The truth is probably less glamorous. Thai dealers had known of Ceylon’s primitive blow-pipe heating. And as the chosen recipient of a personally tailored Marshall-type-Plan courtesy of the Pentagon’s war on the domino-theory, Thailand was a country that was industrializing at miracle speed. In this environment of booming businesses and industry, finding industrial ovens or even just the simple couple-blowers beloved of Chanthaburi heaters to run experiments would of been as easy as making a call on the telephone or flicking through the then Yellow Pages.

Regardless of how, the facts of the results were breathtaking. The glass-ceiling of the temperature-sound-barrier had been broken, and the Kali of Corundum, namely rutile, destroyer of clarity and creator-of-color had been awakened, and bestowed these first Thai heaters with fabulous resplendent blue colors. With the sound-barrier behind them, these businesses literally went into sonic-boom.

An an environment such as Chanthaburi, in the pre-internet era, the gem heating and cutting community was both a work-and-social club. Knowledge was in tidbits glibly dropped, traded over long frequently beers and whisky, for mutual benefit, respect, favors, and out of social obligations. Know how and knowledge radiated out via usual glued and threads of Thai society along lines of family, school, neighborly and other ties, and new relationships transformed via sales and traveling together in foreign lands to purchase rough.

Social proof by mouth and visible edifices of wealth pulled more in. All good things must come to an end, and the frenzied cycle of unrestricted growth hit the resistance of the laws-of-business. Some sold, cheaper, suppliers jacked the price up. The masses had arrived. Every man and his dog was involved and the party of easy money was over.

While the how and who is lost to history, there is an apocryphal code to this tale of who benefited the most that is literally set-in-stone around the city of Chanthaburi. The huge influx of money as a result of the Geuda, understandably sparked a local luxury-property boom. Many of the prime locations in town have, nowhere more so than the “Millionaires Row”, an entire street of large mansions was all built on Gueda money is many period houses built in the 1970’s and 1980’s.

In A Flux – The Rules of The Game Change

Come the 1980’s the city of Chanthaburi had become the global centre for ruby and sapphire. Secondary services businesses sprang-up realizing that in amongst this sapphire-rush fortunes can be made in supply. Chemical suppliers, lapidary services and oven makers were all firmly established and part of the city’s fabric.

With knowledgable consultants and chemical suppliers, the innovators were innovating. Having the learnt the lessons of the fundamentals, which was to find an undervalued product and make it marketable. The search was on for the next Geuda.

Attentions turned to other countries close by and in 1989 / 1990 and seemingly undervalued type of ruby was being quietly bought in the Eastern Shan state. Golden triangle what was connection with the heroin trade of the Golden Triangle which was sharing exactly the same time, space and supply lines of the Mong Hsu ruby trade.

By 1991 it was public knowledge, but for the men who exploited it clandestinely and made the relationships they were now making fortunes and effectively had the industry sown up. Syndicates formed to allow the use of different qualities and sizes.

The first herald of foreign substances

Glass Patching

Beryllium Treatment in Sapphire

unlike beryllium treated sapphires which are. A full look at beryllium treated sapphire can be found here. While it was probably known to the sharper heaters in Chanthaburi, especially those who were connected to the Pump Tanawat syndicate (Werner Spaltenstein et al) who were the largest buyers of chrysoberyl in East Africa at that time.

The first documentation of this was with Gerry Rogers. His apprentice Harvey Bamford.

Ted Themelis, in 2002, in preparation for his book, bought from Don Kogen, chrysoberyl which I was given ward of procuring which I purchased in turn from Werner Spaltenstein.

Enter beryllium powder

Warmer Climes– Low Temperature Heat Treatments & Mozambique Ruby

In Vitro we Trust Lead Glass Treatment in Ruby

Back to The Future — Ruby & Sapphire Treatment to Come


Richard W Hughes.

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