Mineralogical, Physicochemical and Morphological Characterization of Okpella Clay

Local clay mineral was mined from Okpella Town, Etsako Local Government Area of Edo State, Nigeria. Mineralogical characterization of the clay was carried out using X-ray diffraction analyzer. Chemical characterization of the clay was carried out using X-ray fluorescence analyzer and the pH analysis of the clay was carried out using pH meter. The mineralogical analysis revealed that the clay was majorly a dolomite mineral having 72% dolomite. The impurities present are 18% cristobalite, 4.1% garnet, 5% calcite and 1% quicklime. The pH analysis of the clay revealed that the clay was acidic having average pH value of 3.9. The pH determined for the 1:1, 1:2, 1:4, 1:8 and 1:10 samples were 3.61, 3.85, 3.85, 4.05 and 4.09, respectively.

A preliminary study on the element abundance in the Hulusimpang Formation, Way Kalianda, Pesawaran, Lampung, Indonesia

Hulusimpang Formation.has known as Oligocene-Miocene rocks that consisted of volcanoclastic rock. Its scope was wide, especially in southern Sumatra. This formation is supposed as a prospect host of various hydrothermal mineralization. A preliminary study was carried out to examine the abundance of elements located in Way Kalianda River, Pesawaran, Lampung. This study was conducted by easuring its stratigraphy and analyzing its composition using an X-Ray fluorescence analyzer. The lithologies generally consist of lapilli tuffs, volcanic breccias, interbeded by claystone and sandstone; in addition, it is also frequently found petrified wood and andesitic-lithic fragments. As a result, the significant abundant elements are Fe (35.5%), Si (27.9%), Al (17.4%), K (6.7%), Cl (5.5%), Ti (1.7%), and Ca (1.5%) and also Mn, Ag, P, Mg, Sr, Zr, and Co. It also presents trace elements such as Rb, Zn, Pb, Te, V, Ba, Cr, Sn, Ni, Ga, Nb, Mo, and Eu. These elements are suggested from distal facies of intermediates-magma series Tertiary volcano.

Historical lead glass in museum collections: determination of the composition by a portable X-ray fluorescence analyzer

A method for the determination of the glass composition in the systems PbO – SiO2 and K2O – PbO – SiO2 with different additives present both in historical and modern art glass is considered. Development of a non-destructive method for determining the glass composition in conditions of museum storage is an important goal for museum practice. We propose a method for determining the composition of those glasses using a portable X-ray fluorescence analyzer (XRF). To select the optimal software suitable for measurements, we have synthesized a number of standard glass samples with the composition determined by ICP-AES. A glass sample of was dissolved in an autoclave in a mixture of nitric, hydrofluoric, and perchloric acids. The lead content in standard samples was simultaneously determined gravimetrically after fusion of the sample with sodium carbonate. Using XRF measurements of standard samples we development of a method for determination of the glass composition with an accuracy sufficient to assign the glass to one of the groups of historical glasses. The results obtained can be used for attribution of lead glass products. The content of potassium oxide in historical samples was estimated by XRF method using two independent programs with subsequent averaging of the data obtained. When using our method, the error of potassium, silicon and lead determination does not exceed 10%, which is sufficient for a museum description and attribution of an item. The developed procedure was tested in analysis of the items from the collection of the State Museum of Ceramics («Kuskovo Estate of the 18th century»).