Properties of MICA

Physical Properties of Natural MICA

Characteristics Unit Phligophite Muscovite
Chemical Composition
(Less water of hydration)
H2KMg3,Al(SiO4)3 H2KAl3(SiO4)3
Color Amber/Yellow Ruby/Green
Density (Gm/cm3) 2.6-3.2 2.6-3.2
(Lb/In3) 0.095-0.116 0.095-0.116
Specific Heat 0.21 0.21
Hardness Moh Scale 2.3-3.0 2.8-3.2
Shore Test 70-100 80-105
Optic axial angle 7-25 55-175
Tensile Strength Kgf/cm2 About 1000 About 1750
Lbf/In2 About 15000 About 25000
Shear Strength Kgf/cm2 1000-1300 2200-2700
Lbf/In2 14000-19000 31000-38000
Compression Strength Kgf/cm2 1900-2850
Lbf/In2 27000-32000
Modulus of Elasticity Kgf/cm2 x 10-3 1400-2100 1400-2100
Lbf/In2 x 10-6 20-30 20-30
Coefficient of expansion per0C
perpendicular to cleavage plane
9 x 10 -6 -36 x 10-6 9 x 10 -6 -60 x 10-6
Clacining Temperature C 900-1000 800-900
F 1650-1830 1470-1650
Maximum operating temprature C 800-900 600-800
F 1470-1650 1110-1470
Thermal Conductivity Gm.cal/Sec/cm2/C/cm About 0.0001 About 0.0013
Perpendicular to cleavage planes BTU/hr/ft2/Of/ft About 0.24 About 0.31
Parallel to cleavage planes Gm.cal/Sec/cm2/C/cm About 0.012
BTU/hr/ft2/Of/ft About 3.0
Water of constitution % 3.0 4.5
Moisture absorption Very low Very low
Apparent electric strength 0.001" to 0.003" KV/mm 120-200
Thick Volts per 0.001" 3000-5000
R.M.S at 15øC (60øF) 0.001" to 0.003" KV/mm 30-60 40-80
Thick Volts per 0.001" 750-1500 1000-2000
Permittivity as 15øC (60øF) 5-6 6-7
Power Factor (loss tangent) @ 15øC (60øF) 0.001-0.005 0.0001-0.0004
Volume Resistivity 25øC(77øF) ohm cme 1 x 1012 – 1 x 1012 40 x 1013 – 2 x 1017
Acid reaction Affected by Sulphuric acid Affected by Hydrofluoric acid