Physicists and geologists from the USA, Great Britain and Italy discovered and studied in details the new molybdenum mineral - merelaniit. It was named merelaniit, in the honor of the Tanzanian deposite and is like thin black needles, growing on other minerals. The internal structure of the substance looks unusual, it resembles a scroll or a cigar, twisted from sheet of molybdenum sulfide, lead, vanadium and antimony. The chemical composition corresponds to the formula of merelaniit Mo4Pb4VSbS15, however, besides the main components, the researchers found in samples the mixture of arsenic impurity, bismuth, manganese, tungsten, copper, and selenium.