# Gemfields > Gemfields is a world-leading miner and marketer of responsibly sourced coloured gemstones. It is the 75% owner and operator of the Kagem emerald mine in Zambia and Montepuez Ruby Mining (MRM) in Mozambique, and sells rough emeralds and rubies through its own auction process, introduced in 2009. Key facts, each taken from the page linked beside it: - Kagem is an open-pit emerald mine in the southern part of Zambia's Copperbelt, in the Ndola Rural Emerald Restricted Area. Gemfields acquired it in 2008 in partnership with the Government of the Republic of Zambia through the Industrial Development Corporation (IDC). Source: https://gemfields.com/about/our-mines-and-brands/kagem-emerald-mine/ - Kagem recovered the 11,685 carat "Imboo" emerald in 2025. Source: https://gemfields.com/about/our-mines-and-brands/kagem-emerald-mine/ - Montepuez Ruby Mining covers 33,600 hectares in Cabo Delgado province, northeast Mozambique, one of the most significant ruby deposits in the world. Operations began in 2012. Gemfields owns 75%; Mwiriti Limitada, a Mozambican company, owns 25%. MRM employs 1,400 people, 95% of them Mozambican nationals. Source: https://gemfields.com/about/our-mines-and-brands/montepuez-ruby-mine/ - Gemfields auctions rough gemstones sorted and graded by colour, size, shape and clarity. Government representatives from the country of origin seal the gems before export and observe the auction, and 100% of the value is repatriated to the mining company in the country of origin. Source: https://gemfields.com/about/our-sales-process/our-auctions/ - Of circa USD 2.4 billion of Gemfields auction revenue from 2009 to 2025, about USD 504 million (21%) was paid in corporation tax, dividends and mineral royalty to the governments of Mozambique and Zambia. Source: https://gemfields.com/about/our-sales-process/our-auctions/ - The Gemfields Foundation is a UK registered charity (number 1185658). Source: https://gemfields.com/foundation/ Gemfields Group investor information is published separately at https://www.gemfieldsgroup.com. ## About Gemfields - [About Gemfields](https://gemfields.com/about/about-gemfields/): Who Gemfields is, what it does, and its commitment to transparency, legitimacy and integrity. - [Our mines](https://gemfields.com/about/our-mines-and-brands/): Overview of the emerald and ruby operations in Zambia and Mozambique. - [Kagem emerald mine, Zambia](https://gemfields.com/about/our-mines-and-brands/kagem-emerald-mine/): Location, ownership, how Zambian emeralds formed and are mined, and certifications. - [Montepuez ruby mine, Mozambique](https://gemfields.com/about/our-mines-and-brands/montepuez-ruby-mine/): Location, ownership, employment, how Mozambican rubies formed and are mined and sorted. - [Timeline](https://gemfields.com/about/timeline/): Key dates in the company's history. - [Films](https://gemfields.com/about/films/): Gemfields' films about its mines and gemstones. ## How Gemfields sells gemstones - [Our sales process](https://gemfields.com/about/our-sales-process/): How rough gemstones move from mine to market. - [Sorting and grading](https://gemfields.com/about/our-sales-process/sorting-and-grading/): How rough emeralds and rubies are sorted and graded before sale. - [Our auctions](https://gemfields.com/about/our-sales-process/our-auctions/): The auction process introduced in 2009, government oversight and revenue repatriation. - [Authorised auction partners](https://gemfields.com/about/authorised-auction-partners/): The vetted companies that buy at Gemfields auctions. ## Gemstone guides - [Emeralds](https://gemfields.com/gemstones/emeralds/): Emerald colour, characteristics and origin, including Zambian emeralds. - [Rubies](https://gemfields.com/gemstones/rubies/): Ruby colour, characteristics and origin, including Mozambican rubies. - [Gemstone buying guide](https://gemfields.com/gemstones/buyers-guide/): How to judge rubies and emeralds when buying. - [An introduction to coloured gemstones](https://gemfields.com/gemstones/an-introduction/): An overview of coloured gemstones. - [Research and reports](https://gemfields.com/gemstones/research-and-reports/): Gemfields' published research on the coloured gemstone market. - [Special gems](https://gemfields.com/gemstones/gemstone-finds/): Notable emeralds and rubies recovered at Gemfields' mines. ## Responsibility - [Our approach](https://gemfields.com/responsibility/our-approach/): How Gemfields approaches responsible mining and its role in the coloured gemstone industry. - [People and environment](https://gemfields.com/responsibility/people-and-environment/): Workforce, health and safety, and environmental management. - [Community](https://gemfields.com/responsibility/community/): Health, education and livelihood projects around the mines. - [Conservation](https://gemfields.com/responsibility/conservation/): Conservation projects Gemfields supports. - [Industry partnerships](https://gemfields.com/responsibility/industry-partnerships/): Industry bodies and initiatives Gemfields belongs to. - [Gemfields Foundation](https://gemfields.com/foundation/): The company's UK registered charity and the projects it funds. ## News and contact - [News and journal](https://gemfields.com/news/): Company news, gemstone finds and auction results. - [Press](https://gemfields.com/press/): Press releases and media resources. - [Contact](https://gemfields.com/contact/): How to contact Gemfields. ## Optional - [Legal](https://gemfields.com/legal/): Legal notices. - [Chinese-language site](https://gemfields.com/cn/): Gemfields' site in Chinese. - [Gemfields Group investor site](https://www.gemfieldsgroup.com): Investor relations, results and announcements.