The White Sands of Tutong: A high-quality silica sand deposit from Borneo

The iconic White Sands of Tutong in Brunei Darussalam, located on the island of Borneo, have long been heralded as a potential source of glass sand. As Brunei Darussalam tries to diversify its economy, these sand deposits have come into focus as a mineral resource for sustainable development. The white glass sand deposits represent an ancient beach dune system in the Tutong district of Brunei Darussalam, where they are most extensively found. While the sand is often devoid of vegetation, it also supports a rare tropical heath forest, covering an area of around 13 km2 with an average depth of 3 m. Grain size analysis was conducted on selected samples using laser diffraction, and grain size statistical parameters were calculated using Folk and Ward method. The results show that the Tutong White Sand can be characterised as a moderately well sorted fine sand, with symmetrical graphic skewness and mesokurtic graphic kurtosis. The X-Ray Fluorescence (RFA) analysis from the samples revealed that the sand consists of >99.5 wt% SiO2, 0.05 wt% Fe2O3 and between 0.05 and 0.1 wt% TiO2. A glass melt produced from samples showed that the glass was almost clear with only a slight discolouration. Thus, it can be concluded that the White Sands of Tutong are a high-quality quartz sand deposits and, based on its purity, compare well with other international high quality quartz sands deposit.