Lamont was born in Kimberley, South Africa in 1920. At 18, after graduating high school, he attended the University of Cape Town where he studied geology. The outbreak of World War II led him to stop his studies and join the army, however he resumed his studies by 1941. While at the university, he met Dr. Louis Murray. This friendship proved to be a pivotal point for both men, after Dr. Murray became Consulting Geologist to De Beers.
In 1947 he received his PhD, and two years later Dr. Lamont started working at the Bechuanaland Protectorate Department of Geological Survey. The Bechuanaland Protectorate was the British ruled area, later to become Botswana. Six years later and with great familiarity with the local geology, Lamont was recruited by Anglo American, the mining company formed by Ernest Oppenheimer, which already controlled De Beers. The company "lent" him to De Beers to manage their diamond prospecting efforts in Tuli Block, along the country's eastern border.
Lamont realized that the local geology and conditions required them to adapt their exploration methods, which led him to develop a series of systematic indicator mineral exploration techniques suited to work in the Kalahari.
In 1959, three small diamonds were recovered in the Motloutse River, near Foley Siding. They were found by the Central African Selection Trust (CAST) and were the first hard proof that there are diamonds in the region. This gave the De Beers team some back wind, however despite their great efforts, diamonds, or even a kimberlite resource, eluded them. CAST was disbanded and De Beers, which assumed that the diamonds drifted to the site, looked at other parts of the region to find the elusive resource. In 1964, Lamont decided to return to the site of the original CAST discoveries. He further studied CAST's findings and continued searching for diamonds where they found the first three stones.
In 1967, a year after Botswana declared its independence, luck struck and the Orapa diamond resource was discovered. How lucky was this discovery? Orapa is located in a very remote area of Botswana, about 250 miles from the capital city Gaborone. De Beers had been prospecting for diamonds in the area since 1955. After 10 years of long and unsuccessful exploration, the mining giant was about to give up and move on. However, its lead geologist, Dr. Gavin Lamont, was sure that the region was rich with diamonds, and that the company should push on. He convinced his old friend Dr. Murray to continue searching for one more season. If diamonds were not found by the end of winter 1966, De Beers would pull out, and exploration would end.
Two months before the deadline, the team found the first kimberlite pipe in the Mochudi area. Although the resource was not significant in and of itself, it was promising enough for the company to extend the deadline. Not long after, diamonds were discovered at Orapa. Four years after the discovery, and with an investment of $33 million in developing the resource, the Orapa diamond mine was ready for production.
Dr. Lamont did not rest. He understood from the data he gathered that additional diamond pipes should be found in the area. Later that year, he was proved right when he discovered the resource now known as Letlhakane. A few more years of research and prospecting led to the 1973 discovery of the richest diamond resource ever found, Jwaneng.
"Doc was a firm believer that mines were to be found not by spending time in town or office, but by 'boots on the ground,' and careful understanding," De Beers said about him a few years later. What made his findings especially impressive are the tools that were at his disposal – or lack thereof. Computerized analysis was not made available to them, GPS tracking did not exist, aerial magnetic detection was not invented yet, and today's geophysical technologies were not developed. And yet, he succeed in making these remarkable discoveries while being out in the field.
His findings turned the diamond industry around. At once, the volume of diamond production increased, setting the stage for wider availability of polished diamonds to consumers, and ultimately to a decrease in the price of polished diamonds.
The dramatic change for the diamond industry had far-reaching implications for Botswana. The poor country, suffering from frequent droughts, was elevated into a very different place. By adopting policies that led to the careful development of the diamond resources as a long-term asset, and successfully negotiating major investments in the country with De Beers, with a focus on infrastructures, Botswana set itself as a shining example of how natural resources can elevate a country and its people.
Botswana reached an agreement with De Beers for a 50/50 partnership in the ownership of the diamond mining company that would develop and mine these resources – Debswana. Coupled with diamond royalties and labor salaries, Botswana under the leadership of President Khama became one of the most economically successful resource-dependent countries in the world, and this could not have happened without "Doc" Lamont's discoveries.
In 1977, President Khama awarded Dr. Lamont the Presidential Order of Honor in recognition of his contribution to the nation. In 1980, after 25 years of service for and in Botswana, Dr. Lamont retired and returned home to Cape Town. In April 2008, following a long battle with cancer, Dr. Lamont died at the age of 87, leaving behind him a legacy of hard work, contribution and knowledge.