Boart Longyear samples for the proposed Golden Gate Bridge in San Francisco. In spite of the financial crisis, the 1930s saw improvements in diamond drilling technology, including the use of industrial-quality diamonds mined in Africa that were called “boarts.” In 1936, South Africa’s Anglo American Corporation formed Boart Products South Africa (Pty) Limited, which was later named Boart International. The new company developed the first mechanically-set diamond core bits, which were less expensive than the hand-set core bits that used more expensive Brazilian diamonds (carbonados). Longyear’s business gradually improved in the 1940s in response to expanding worldwide mineral exploration. In 1949, the
Teisserenc de Bort (crater) Teisserenc de Bort (crater) Teisserenc de Bort is an impact crater on Mars, located in the Arabia quadrangle at 0.4° N and 315.0° W. It measures 119 kilometers in diameter and was named after French meteorologist Léon Teisserenc de Bort (1855–1913). The name was adopted by IAU's Working Group for Planetary System Nomenclature in 1973. The crater are one of a few that covers the four quadrangles, parts of the crater are in the Iapygia, Syrtis Major and Sinus Sabaeus quadrangles, the crater's center is in the Iapygia quadrangle. Nearby prominent craters include Schroeter (or Schröter) to the east, the