%************************************************
% Define elastic stiffness tensor (GPa)
%************************************************
%
% Reference Elastic constants
% Muscovite Vaughan and Guggenheim JGR 1986
%
% Reference Crystal Structure
% Rothbauer, R., (1971) Untersuchung eines 2M1-Muskovits
% mit Neutronenstrahlen, Neues J. Mineral. Monal., 143-154.
% Muscovite C2/c x||a z||c*
% KAl2AlSi3O10(OH)2  2M1 
% Define density 2.834 (g/cm3)
rho= 2.834;
%
% Define Cartesian Tensor crystal symmetry & frame
cs_Tensor = crystalSymmetry('2/m',[  5.1918 9.0153 20.0457],...
 [  90.00  95.74  90.00]*degree,'x||a','z||c*',...
 'mineral','Muscovite');
%
% elastic Cij stiffness tensor (GPa) as matrix M
 M =.... 
 [[  181.00   48.80   25.60    0.00  -14.20    0.00];...
 [    48.80  178.40   21.20    0.00    1.10    0.00];...
 [    25.60   21.20   58.60    0.00    1.00    0.00];...
 [     0.00    0.00    0.00   16.50    0.00   -5.20];...
 [   -14.20    1.10    1.00    0.00   19.50    0.00];...
 [     0.00    0.00    0.00   -5.20    0.00   72.00]];
%
% M as stiffness tensor C with MTEX tensor command
C = tensor(M,cs_Tensor);
%
