According to reports, the 32-year-old tourist, accompanied by another Chinese man, asked Suresh de Silva, director of the Belgrade International gem store in Colombo, if he could inspect the diamond.
After he ate the 7.2-millimeter wide precious stone, he was quickly arrested and taken to the Colombo National Hospital, where he is scheduled to be administered laxatives in order to “flush out” the diamond.
However, X-rays indicated that the diamond is trapped in his gullet and might be very difficult to extricate.
"Doctors have advised surgery to remove the diamond," a police spokesman named Ajith Rohana told Agence France Presse.
"The man's life could be in danger if the pointed end of the diamond tears his guts. We have already informed courts about this. For the man's own safety, he will have to undergo surgery."
The unnamed Chinese man is now in police custody. He is likely to face theft charges once the diamond is jettisoned from his body.
Almost two years ago another diamond swallower made news in nearby India, but he was far more ambitious (and had a much bigger appetite).
In October 2010, a Sri Lankan man named Mohammed Shakif tried to smuggle 2,060 diamonds valued at $670,000 out of the airport in Chennai, India by swallowing the stones packed in 42 condoms.
He was arrested and taken to the police station where he was x-rayed.
Shakif, then 43, confessed that he was hired to smuggle the diamonds and would have received a commission of about $224b for each batch he delivered.
“Even during questioning, he could not sit comfortably and when questioned, he told the police that he was suffering from piles,” Police commissioner SR Jangid told Indian media.
“He had previously smuggled in three occasions in a similar manner and was caught this time. We got a tip-off that he would be about 40 years old and has a gap between his two front teeth. We waited at the immigration check and nabbed him as he was about to get into a taxi.”
Reportedly, the diamonds were “recovered” only after Shakif ate a substantial amount of bananas (a natural laxative).
Precious gems and jewelry are big business in Sri Lanka and stretch back to the island nation’s antiquity.
According to the Sri Lanka Export Development Board, the industry employs about 600,000 people, including miners, cutters and polishers, dealers, jewellery designers, manufacturers and craftsmen.
In 2010, Sri Lanka exported about $476 million in gems, jewelry and diamonds.