. With respect to composition, each series of MgO particle size has a specific composition needed to achieve the optimum density value. For samples with 500 nm and 7000 nm MgO as additives, more than 0.7 wt.% of MgO will produce continuously decreased values which are not significant for discussion. With respect to composition, a study conducted by Azhar et al. and Rittidech et al. also showed similar trends.