As part of its mission to ensure and maintain public trust in gems and jewellery, GIA (Gemological Institute of America), regularly sends field researchers to different mining areas the world over.

In September, a team of field researchers – including field gemmologists Vincent Pardieu and Andrew Lucas, Gems & Gemology (G&G); technical editor Tao Hsu; videographer Didier Gruel; and expedition guest Stanislas Detroyat – went to Zambia to collect emerald samples for the institute’s gem identification database and to document the current state of Kagem, the world’s largest emerald mine, located in the Kafubu mining area. GIA noted that since Gemfields acquired the open pit mining operations six years ago, ore mining has increased from 3,000 to 8,000 tons per month and rock handling has increased from 125,000 to 750,000 tons per month.

“I’ve visited numerous coloured gemstone mining operations throughout the world, but one of this size, modernisation and organisation really gives a visual of the changes that may be coming to our industry,” said Lucas.

The team found that the mine-to-market gemstone business has been “revolutionised” by the implementation of a standardised grading system for emerald rough and an auction platform, environmentally sound practices and community outreach programmes.

“Standing in front of the pit is like looking at a geological textbook,” commented Detroyat.  The team’s report said that “By combining an understanding of geology with professional mining methods, Gemfields has turned Kagem into a profitable operation. In July 2009, its first high-grade rough emerald auction achieved $4.4 million, and in February 2014, $59.31 million.”

After their visit to Kagem, the team went on to study other Zambian emerald mines to collect comparative samples. The team confirmed that the small mining operation of Musakashi in the Solwesi province, did indeed have an emerald deposit “with interesting internal features and colour reminiscent of Colombian emeralds as reported in the summer 2014 issue of G&G”. The team noted that several other operations in the Kafubu area, such as Miku, Dabuisha, Matenke and Benisa, are now run by Chinese companies.