MINERALIZATION OF TUNGSTEN AND RARE EARTH ELEMENTS IN GRANITE VARIETIES AT THE TIKUS DEPOSIT OF THE TANJUNGPANDAN PLUTON, BELITUNG, INDONESIA
The Tikus deposit is the most important primary ore deposit hosted by granite within the Tanjungpandan pluton on the “tin island” of Belitung, Indonesia. Although the site is known for its tin, its several granite varieties have been shown to host economic deposits of tungsten and rare earth elements (REE). Given the current surge in technology, the demand for these specific elements will encourage future exploration programs. Geochemical surveys were conducted on Mount Tikus and surrounding locations within the Tanjungpandan Pluton in July 2017, yielding 18 rock chip samples of several granite varieties. Optical mineralogy (petrography and mineragraphy), reflectance spectroscopy interpretation, and inductively coupled plasma mass spectrometry (ICP-MS) were carried out to detect the alteration and mineralization types within the pluton and to measure the geochemical patterns of both tungsten and REE. The enrichment of REE was presumably caused by the identified existence of accessory minerals (allanite, zircon, monazite, and apatite) in the rocks. Tungsten, along with tin, was present in fine-grained cassiterite–wolframite mineralization, which was disseminated in greisen. Tungsten was also found in the mineral scheelite in the greisen phase. This information will assist in the development of exploration models for future mining ventures at the Tanjungpandan pluton.