BANGKOK — Human rights activists are lobbying major jewelers to stop buying gems sourced in Myanmar as a way to exert pressure on Myanmar’s military leaders by limiting profits from the country’s lucrative mining industry.

A report by the group Global Witness released Wednesday outlines how the army is involved in gemstone mining despite a moratorium on new licenses put in place before the military seized power on Feb. 1, ousting the government of Nobel Peace laureate Aung San Suu Kyi.

It comes as legislation is pending in the U.S. Congress, the Burma Act of 2021, which would prohibit all U.S. imports of Myanmar gemstones.

“There is no such thing as an ethically sourced Burmese ruby,” Clare Hammond, senior Myanmar campaigner at Global Witness, said in a statement. “These gemstones are sold as symbols of human connection and affection, yet the supply chain is steeped in corruption and horrific human rights abuses.”

Last week, luxury jeweler Harry Winston announced it would no longer buy gemstones with Burmese origins regardless of when they were imported.

Indian jewelry company Vaibhav Global said in late November it had removed all listings of products including Myanmar gems while it investigates their sourcing. Vaibhav’s products are sold widely online, including on Amazon, Overstock and Walmart’s sites.

Tiffany & Co. never resumed using Burmese gems after U.S. sanctions against Myanmar were lifted in 2016 when the country was in the midst of political and economic reforms following decades of military rule. Cartier, Signet Jewelers – the owner of the Zales, Kay Jewelers and Jared chains – and Boodles also have declared they are not sourcing gemstones from Myanmar.

But prized Burmese “pigeon blood” rubies and other beautiful gemstones are easily available on many e-commerce sites, as are costly items of jewelry adorned with gems from strife-torn Mogok and other mining areas.

Global Witness and other groups are urging all retailers of gems and jewelry to follow suit in halting purchases and sales of such products, describing the jade and gemstone sector as one of the military’s most important sources of funding, especially following the takeover 10 months ago that has ignited widespread political turmoil.

Smuggling and illicit sales make it hard to know exactly how big the industry is, but revenues from sales of jade, pearls and gemstones are estimated to run into the billions of dollars.

Myanmar’s “natural resource wealth is proving to be a lifeline for the generals,” the report says. “For decades the military has consolidated its rule by looting the country’s valuable natural resources.”

Confronted with widespread public opposition to their seizure of power, the military has engaged in mass torture, launched attacks on medics and forcibly disappeared thousands of people. Since February, soldiers and police have killed at least 1,300 people and arrested more than 10,800, according to the Assistance Association for Political Prisoners, which monitors deaths and arrests.

Two state-run Myanmar conglomerates, Myanmar Economic Corp. and Myanma Economic Holdings Ltd., dominate the jade and gems trade through various subsidiaries. Other gem traders are thought be associates of Senior Gen. Min Aung Hlaing, who led the military takeover.

The U.S. and other governments have imposed sanctions on some military-affiliated companies, army leaders and their families. One of the companies subject to sanctions is Myanma Gems Enterprise, which is in charge of licenses and permits for mining gems and jade and collects revenues from their sale.

The Global Witness report, which analyzed official data, estimates that the gemstone industry alone generated revenues of $346 million to $415 million when it was in full operation, though much of the gems trade is conducted through illicit channels.

Suu Kyi’s government suspended renewing or granting new licenses in 2016 and the last existing license expired in 2020. So mining activity now is unauthorized, or at least not based on publicly disclosed licensing.

Much of the mining is in Mogok township, where most of Myanmar’s rubies, sapphires and other gems are unearthed. With big operators not in business, mining is mostly done by hand under perilous conditions, the report said.

Many gemstones are processed in Thailand and by the time they are imported their origin has become unclear, it said.