Many US and European jewellery companies, including Bulgari, Tiffany, and Cartier, refuse to import these stones based on reports of deplorable working conditions in the mines. Human Rights Watch has <answer>encouraged a complete ban on the purchase of Burmese gems based</answer> on these reports and because nearly all profits go to the ruling junta, as the majority of mining activity in the country is government-run. The government of Myanmar controls the gem trade by direct ownership or by joint ventures with private owners of mines.
What did the group advised based on the information's results ?
encouraged a complete ban on the purchase of Burmese gems based