In exploration, the investigation of prospective area encounters several barriers of land ownership, budget limitation, and exhausting permit procedures. To speed up the exploration activities of bauxite deposits and bauxite characteristics, grades of the gap areas should be simulated based on the available test pit data sets. This study aims to address the limitations and to optimize the exploration boundaries using the R project for statistical computation. R data analysis weaves the framework of kriging that required information from the adjacent data. This study utilizes the geochemical data of Al 2 O 3 , Fe 2 O 3 , SiO 2 , and TiO 2 from 296 test pit sampling points. The geochemical data used for R analysis were taken from bauxite horizon, while the other mineralogical properties were taken entirely from the exposed bedrock and test pit data. To verify the result of R analysis, recent data of the simulated area were used as a comparison. The R result shows the prediction value is slightly below the actual value of Al 2 O 3 . The kriging simulation of Al 2 O 3 was correlated with test pit and mineralogical characteristics of samples. This reveals the predicted value of simulation closely represents the true value of Al 2 O 3 grades. Extrapolation results of Fe 2 O 3 and RSiO 2 with regards to Al 2 O 3 grades suggest that higher grade of bauxite underwent desilication and deferruginization as evidenced by a high value of Index of Lateritization. It can be inferred that this attempt points out the advantages of a quick and reliable projection of bauxite laterite deposits from the limited parameters

High demand in utilizing the mineral and metal for industrial manufacture, which is unequal to the resources, has caused a vulnerable disruption. To compensate stocks in the global market, exploration of raw materials should be carried out for by-products. This study aims to elucidate the enrichment mechanism of Sc, Ga, and Nb elements from the bauxite weathering profile and sediment residue. An observation has been conducted using petrography, mineragraphy, x-ray fluorescence spectroscopy (XRF), x-Ray diffraction (XRD), inductively coupled plasma combined with mass spectrometry (ICP-MS), and scanning electron microscope - energy dispersive spectrometry (SEM-EDS). The results indicate that bauxite ores (gibbsite) hold the metal compounds of Ga, while some iron minerals of goethite and hematite are present as Sc-bearing minerals, and Nb is highly concentrated within saprolite of bauxite. The maximum enrichment of Ga and Sc is observed from the bauxite sample and sediment residue derived from microdiorite pyroxene, which makes up 24.2 - 42.1 ppm and 39.9 - 55.4 ppm, respectively. By contrast, Nb enriched about nine-fold higher in the saprolite zone relative to bauxite produced by weathering of granitic parent rocks. It suggests that metal concentration in the lateritic products depending immensely on the precursor rock types.

Situating in a tropical climate, will be favourable for Indonesia and Malaysia to have an intensive weathering and a concentration of lateritic bauxite. The study area takes place in Kuantan, Pahang State, Malaysia and Landak area, West Kalimantan, Indonesia. The study area has different type of parent rock, topography and drainage condition, which will also cause the different characteristics of alumina minerals in bauxite. One of the common form of alumina minerals is known as Gibbsite [Al(OH)3]. The objective of this research is to investigate the genesis of gibbsite from two different parent rocks. Samples were taken and collected from pitting, analyzed for Al2O3, Fe2O3, SiO2 and TiO2 using XRF and XRD examination. The parent rock of bauxite in Kuantan is basalt, meanwhile, in Landak, ranges from granodiorite to andesite. Petrography and XRD analyses of Kuantan bauxite shows predominant gibbsite, with minor amount of geothite, hematite, kaolinite, illite, quartz and feldspar, while in Landak, mineralogically consists of variant amount of gibbsite, goethite, hematite, kaolinite, illite and quartz. In Kuantan, the amount of Al2O3 varies from 23.6% - 51.01%, nearly similar than that in Landak that varies from 31.35% - 55.03%. Gibbsite in Kuantan is assumed as a transformation of Ca-rich plagioclase and Ferromagnesian- silicate minerals, on the other hand, gibbsite in Landak was produced from direct weathering of primary Al- silicate minerals (Na- plagioclase and K-feldspar). From study, it can be inferred that gibbsite formed from a layer of silicates and will concentrated in finer clay as a weathering product. Moreover, the different types of parent rock will produce different types and amount of alumina minerals. The study will be beneficial to predict the existence of potential alumina minerals in lateritic bauxite.

The lateritic bauxite deposits in the Mempawah area, West Kalimantan, were formed by the chemical weathering of Cretaceous granodioritic and andesitic rocks. They occurred locally on the low hills surrounded by swampy areas. Detailed surface geological mapping, test pits, mineralogical and geochemical analyses were performed to determine the characteristics and genesis of bauxite from different parent rocks. From bottom upward, the deposits are composed of fresh parent rocks, clay or pallid zone, bauxite zone with a few sparse ferricrete at the top of the bauxite zone, and soil. Bauxite derived from granodiorite exhibits brownish-red, massive, boulder to gravel-sized concretion in clay matrix and is composed of predominant gibbsite with subordinate kaolinite, quartz, goethite, and a minor amount of magnetite and hematite. In contrast, bauxite derived from andesitic rocks exhibits reddish-brown and is composed of predominant goethite. During the leaching process, SiO2 as a mobile compound decreased significantly in neutral pH, while Al2O3 and Fe2O3 precipitated as residual materials to form bauxite concretion. The enrichment anomaly of bauxite derived from andesitic rocks is caused by physio-chemical changes from hydrothermal alteration. Bauxite was formed by indirect bauxitization through the leaching of primary minerals under a tropical-humid climate.

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