Variation of the elastic constants of tourmaline with chemical composition

Elastic wave velocities and lattice parameters of five tourmaline specimens with different chemical compositions have been measured. The piezoelectric effects on the elastic constants have been found to be small and can be neglected. Variations of the elastic wave velocities and elastic constants of the different tourmaline specimens indicate that: (i) partial substitution of Al by Fe in the structure decreases the shear wave velocities, (ii) replacement of Na by Ca increases the resistance of the structure against shear deformation involving C 66, (iii) replacement of Al by Mg seems to decrease the resistance of the structure against longitudinal deformation involving C 33. Elastic constants C 11, C 33, C 44 and C 66 of the different tourmaline specimens used in this study differ individually by 1.7 percent to 6.7 percent, indicating that the large differences (up to 21%) between the values reported by previous authors cannot be explained in terms of the chemical composition alone.
Physics and Chemistry of Minerals


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Elastic wave propagation through an area discontinuity of two dissimilar, bonded, semi-infinite circular rods is investigated analytically. In particular, the variations of the coefficients of stress reflection and transmission are determined in terms of the nondimensional cross sectional area and mechanical impedance parameters. The coefficients of energy flux reflection and transmission are also included. Then, the case is generalized to include a rigid mass attached at the discontinuity.
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Propagation of two-dimensional transient out-of-plane shear waves in multilayered viscoelastic media is investigated. The multilayered medium consists of N different isotropic, homogeneous and linearly viscoelastic layers with more than one discrete relaxation time. The top surface of the layered medium is subjected to dynamic out-of-plane shear tractions; whereas, the lower surface is free or fixed. A numerical technique is employed to obtain the solution, which combines the Fourier transform with the meth...
Citation Formats
A. Tatli and Y. Galioğlu Özkan, “Variation of the elastic constants of tourmaline with chemical composition,” Physics and Chemistry of Minerals, pp. 172–176, 1987, Accessed: 00, 2020. [Online]. Available: