Thayer Lindsley, a mining executive, was born in 1882 in Yokahama, Japan to American parents. He studied civil engineering at Harvard and did post graduate work in geology at Columbia University. He made his first mining profits in the Pacific Northwest and northern Ontario in the early 1920s and in 1928 founded Ventures Ltd., a Canadian holding company with worldwide mining interests. At the height of his career, Lindsley held the presidency of 10 mining companies, directorships in 15 others, and controlling interests in another 40 companies. He retired as president of Ventures in 1955 and as president of Falconbridge Nickel Mines Ltd., Venture's principal subsidiary, in 1956. Lindsley remained interested in mineral exploration until his death in 1976.

Thayer Lindsley, one of the 20th century's most prominent mine developers, was born on August 17, 1882, of American parents in Yokohama, Japan. When he was fifteen years old the family returned to the United States and settled in Milton, Massachusetts.

Mr. Lindsley graduated from Harvard with an A.B. in 1903 and as a civil engineer in 1904. One of his classmates was Franklin D. Roosevelt with whom he corresponded until the President's death. His first job out of college was helping to construct the Brooklyn-Manhattan subway with the engineering department of the New York City Rapid Transit Commission. This job, and incentive from his older brother, Halstead, a mining engineer, made Mr. Lindsley decide on a career in mining.

Besides several months study of geology at Columbia University in 1910, Mr. Lindsley spent the years 1904 to 1917 visiting mining camps and prospecting in the western United States and Canada.

World War I interrupted his work when he served in the United States Army as an artillery officer (Capt. C.A.C.). As soon as the war ended, however, he acquired an unproductive mine in Oregon called the Homestead Iron Dyke Mine and turned it into a profitable enterprise. He sold the mine in 1923 for $30,000, thus beginning his career in mining finance. He then bought the Sherrit Gordon Copper and Silver Mine in northern Manitoba, Canada. Within twenty years he turned it from an unprofitable venture into one of Canada's most productive mines.

With the idea of creating a speculative holding company for mining exploration and development, Lindsley founded Ventures, Ltd., in 1928. In spite of shareholder's protests he purchased 2/3 interest in the idle Beattie Gold Mine. He increased the mine's mining and milling efficiency so that 15 years later it was among Ventures' top money-makers.

Mr. Lindsley's Metal Hydrides subsidiary in Massachusetts was one of the producers of pure metallic uranium for the first atomic bomb. In World War II it also made available sufficient calcium hydride for the needs of the United States Signal Corps, with some surplus for Britain's Royal Air Force.

During this period he established a second mining exploration holding company, Frobisher, Ltd., under the parent firm Ventures, Ltd. The creation of Frobisher, Ltd., allowed Lindsley to expand his world-wide search for ore deposits. After World War II he obtained the Giant Yellowknife Mine in Canada. Within ten years he made it one of the country's five leading gold producers.

By 1951 Mr. Lindsley was president of ten mining companies and on the boards of fifteen others. He was also a director of Canada's Crown Trust Company. His mining enterprises extended over five continents. In the spring of 1952 he became chairman of the board for Williston Oil and Gas Company.

By the fall of 1955, when he retired as president of Ventures and was named chairman of its board, the holding company reportedly had in its portfolio fifteen operating companies, 20 development companies, and around 145 mining, metallurgical, and research companies. Also in 1955 Mr. Lindsley and his brother bought the Falconbridge Nickel Mines in Canada for $2 million. It became the world's second largest nickel producer and the basic source of his personal fortune.

In 1961 Ventures, Ltd., merged with Falconbridge Nickel Mines, Ltd., and Mr. Lindsley retired from the firm. He maintained an active interest in mine financing and exploration, however, until his 90th year. A friend once summed up Lindsley by saying, "His work is studying his own mines. His relaxation is studying someone else's."

Mr. Lindsley married Ida Ann Machin on May 28, 1929, in Kenora, Ontario. The couple were divorced in 1935.

Thayer Lindsley died at his home in New York City on May 29, 1976, at the age of 93. Thayer Lindsley was inducted in the Canadian Mining Hall of Fame in 1989 and there is also an award for international mineral discovery, that bears his name.