One of the most enduring and spectacular mysteries in Asia - which involved the Thai and Saudi Arabian royal houses, several murders, and the theft of jewels that included a magnificent 50 carat blue diamond - may have been put to rest with the January visit of Thailand’s prime minister Prayuth Cha-ocha to Riyadh, according to multiple diplomatic and other sources in Bangkok.

While there is speculation in Bangkok that the agreement, under which the two countries agreed to exchange ambassadors and normalize relations after three decades of estrangement, will allow for the return of the famed diamond, other sources say the Saudis may have decided the benefits of normalization outweigh their continuing anger over the gems’ disappearance. The sources say King Maha Vajiralongkorn played a role in the negotiations.

In what has become known as the Blue Diamond Affair, widespread rumors in Bangkok are that the gem was presented to Queen Sirikit, the wife of the late King Bhumibol Adulyadej, by top officials of the Thai police, which would explain why the Saudis saw the affair as going to the very top in Thailand and wasn’t just some heist by rogue cops. The queen, now 90, suffered a massive stroke some time ago and is unresponsive. Rightly or wrongly, Sirikit acquired the nickname the Blue Diamond Queen because of a belief she had the stone.

“When Bhumibol celebrated his Diamond Jubilee inviting all the monarchs in the world to the party in Bangkok, the Saudi monarchy refused to send someone,” said a former diplomat, apparently because of Riyadh’s belief the royal family had the gems. 

“The person who was in possession of the cursed jewelry is in a vegetative state and would have no qualms in having it taken away and returned to the rightful owner,” said another well-placed source. “The return of the jewelry is peanuts compared to the benefits Thailand can reap, e.g. normalization of relations, return of Thai workers, using the Saudis to intercede with the US and the West to go easy on a partial boycott of Thailand due to the military coup and violations of human rights, use Saudi influence to solve restive South, strengthen the Thai monarchy, etc.”

The gems were stolen in 1989 by a Thai gardener named Kriangkrai Techamong, who is said to have propped a ladder against the wall of the palace of Prince Faisal bin Fahd, ascended to the bedroom and made off with 91 kg of jewelry and other valuables including the 50-carat Blue Diamond, one of the world’s most expensive gems. By comparison, the 42.5-carat Hope Diamond in the Smithsonian Institution in Washington, DC is worth US$400 million.

According to widespread reporting both in Thailand and the Middle East, Kriangkrai hid the jewels in a vacuum cleaner bag and shipped them to his home in Thailand, where he began selling them off for what was described as a pittance. A Bangkok jeweler, Santhi Sithanakan, learned of the sales and bought most of the gems from Kriangkrai at a fraction of their value. Authorities were onto them quickly and Kriangkrai was arrested and ultimately sentenced to seven years in prison although he only served three after he cooperated and confessed. He has since become a monk to atone for his sin.

A Royal Thai Police investigation team headed by Lieutenant-General Chalor Kerdthes flew the stolen gems back to Saudi Arabia. But the Saudis quickly discovered that the Blue Diamond was missing and that about half of the gems returned were fake. According to a report by British journalist Andrew Marshall, rumors spread in the local press that charity gala photos captured high-ranking government wives wearing diamond necklaces resembling those stolen from the Saudi palace.

The Saudi efforts to recover the jewels set off a round of murders in Bangkok including a Saudi diplomat who was found murdered on January 4, 1989 in the Silom district of Bangkok. Three other diplomats were killed in Bangkok’s Yannawa district and in 1990, yet another Saudi was believed to have died in the search for the gems. He was Mohammad al-Ruwaili, a businessman close to the Saudi royal family who traveled to Bangkok to investigate but disappeared. His body has never been recovered.

Newspapers across the Middle East accused the Thai police of the murders and the theft of the gems. Indeed, Chalor, the police general who flew the fake gems to Saudi Arabia, was later convicted and sentenced to death for ordering the murder of the wife and son of a gem dealer allegedly involved in the affair although his sentence was reduced to 50 years imprisonment by King Bhumibol on the late king's 84th birthday. Six other police officials were also convicted of involvement and sentenced to prison.

But the gems never turned up. Eventually, the Saudis stopped issuing work visas for Thais and discouraged their citizens from visiting Bangkok although robed Saudis continued to visit the fleshpots in the city. With diplomatic missions downgraded to the chargé d'affaires level, the number of Thai workers in Saudi Arabia, particularly from Thailand’s restive Muslim south, fell from 150,000-200,000 in 1989 to just 1,350 in 2021, employed mainly as welders, technicians, and household staff. The cost to Thailand was billions of baht in remittances.

“Foreign Minister Don Pramudwinai's strong emphasis on putting everything firmly in the past reveals the real impetus for this sudden rapprochement between Thailand and Saudi Arabia after so many years,” said a knowledgeable western observer in Bangkok. “This is an alliance of desperation, reflecting that both the Thai king and the Saudi crown prince need all the friends they can get because both lack credibility and popularity with global audiences as well as their own people.”

Letting past bygones be bygones and rebuilding a political relationship might be helpful for both sides at some time in the future, the source said. “Prime Minister Prayuth was just sent to sign the deal that was already concluded at higher levels, reflecting his role as a glorified messenger of the palace rather than as an official who had anything to do with this so-called ‘success’ of Thai foreign policy.”

But, he said, it’s unlikely that the floodgates will now magically open for Thai migrant workers to go to Saudi Arabia. Migrant workers from many other countries around the world have already taken the place that Thais were forced to leave 30 years ago.

Nonetheless, Tourism and Sports Minister Phiphat Ratchakitprakarn told local media the government expects to attract at least 200,000 Saudis to Thailand and generate Bt20 billion in revenue in 2022. Although the Saudi government only allowed its citizens to visit Thailand for “medical treatment and official business and governmental affairs,” with pleasure visits strictly prohibited, as many as 37,000 Saudis arrived in 2019, generating about Bt3.2 billion in revenue, he said.

“The visit of Prayuth to Saudi welcomes a new era in this bilateral relationship. I assumed that the Saudis gave up and wanted to go ahead with normalization, particularly reconnecting with the Thai monarchy under Vajiralongkorn,” said Pavin Chachavalpongpun, a Thai professor at Kyoto University in Japan and an opponent of the regime. “At the end of the day, the two monarchs share ruthless tactics in dealing with their opponents, hence the illiberal standpoint seemed to jell them together. Surely, there are other benefits, economic and tourist, to be gained.”

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