A collection of albumen prints, measuring approximately 240 x 180 mm., with detailed captions on the reverse, which are signed 'A.W.I.' The captions have been recorded as found and may contain offensive, inappropriate or outdated terms. They have been retained to reflect the context of the collection's creation. The views show antimony workings in the Jambusan Valley and the cinnabar mining area at Tegora Hill. The detailed pencilled captions on the reverse Cinnabar, the sulphide from which mercury is obtained, was discovered at Tegora by L.V. Helms, the first manager of the Borneo Company, in 1867; mining was begun immediately and exports of the mineral were made from the following year. After a boom period in the 1870s, output was negligible by the 1890s and later ceased almost entirely. The antimony industry was of greater antiquity in Sarawak, having been mined in the Bau area from 1823; the Jambusan Valley was one of the principal sources for the mineral in Sarawak. Output rose rapidly after 1868, peaked in 1872 and remained the leading exported mineral until the mid-1880s. The industry lost all importance about 1916. The dating of these prints relies on the captions to prints 1 and 2, which state that the views show the 'first opening' and 'opening' of the cinnabar mines. The note to print 2 is dated 1880, however, and it is possible that the photographs relate to a slightly later period.