Elastic properties of tektites measured by resonant sphere technique

A new technique for determining elasticity and anelasticity of small spheres, called the resonant sphere technique, is very useful in measuring the elastic constants of small specimens. We have used this technique to measure the elastic properties of two kinds of tektites. The shear and longitudinal sound velocities for a moldavite were found to be 3.627 and 5.918 km/sec, respectively, and those for an indochinite were 3.638 and 5.999 km/sec, respectively. The annealing points of these tektites were also obtained by determining the shear sound velocities of tektite specimens quenched from various temperatures. They are 750°C for a moldavite and 710°C for an indochinite. The temperature variations of shear sound velocity and Poisson's ratio were also determined from room temperature to 130°C. These results show that the resonant sphere technique is a valuable tool for tektite research.