Rio Tinto opened a $2.2 billion diamond mine in Western Australia this week with a ceremony for indigenous beliefs to ward off evil spirits. The site is located in Argyle, Kimberley, which supplies 90% of the world’s extremely rare pink diamonds.

The event marks Rio’s move into underground mining at the site. Following 30 years as an open-pit project, it is anticipated to extend its life to at least 2020, according to Kim Truter, mine managing director. Despite the expansion, Rio will sell the mine, however, even though it has produced 800 million carats to customers in Japan, the U.S., India, China and Australia.

In Q1 2013, Rio officials reported a historic 2012 loss of $3 billion, prompting a full strategic review across sectors—including a $2 billion float of its entire diamond business, including assets in Canada. Rio Tinto is one of the world’s biggest producers of rough diamonds, producing 20% of the world’s supply by volume.