# Elastic Modulus of an Anisotropic Crystal

1. ### Zythyr

32
If I am given that mica has a modulus of 52GPa parallel to the c-axis and 179 GPa perpendicular to the c-axis, how do I figure out the elastic modulus of a polycrystalline mica where grains are oriented randomly?

2. ### Mapes

2,532
You want the Voigt and Reuss averages, which should bound the actual value. I haven't worked through these calculations myself, but this should give you something to search for. See here, for example.