Hardness Mohs: 4 Unit Volume by Weight gr/cm3: 2,70Density gr/cm3: 2,71Water Absorption at Atmspheric Pressure By Weight(%): 0,2 By Volume(%): 0,6Water Absorption at Boiling Water By Weight(%): 0,2 By Volume(%): 0,5Porosity (%): 0,6Compressive Strenght kgf/cm2: 1.020Compressive Strenght After Freezing kgf/cm2: 1.020Strenght to Blow kgfxcm/cm3: 10Strenght to Bending kgf/cm2: 130Modules of Elasticity kgf/cm2: 7,12x104 Ratio of Fullness (%) 99,6Degree of Pores (%) 0,4Average Abrasion Strenght cm3/50cm2 16,7Average Tensile Strenght kgf/cm2: 71CHEMICAL ANALYSIS (%)SiO2 1,27Fe2O3 0,77CaO 53,5MgO 0,53