Single crystal gallium gadolinium garnet (Gd3Ga5O12 or GGG), which crystallizes in the garnet structure at ambient conditions, was observed to transform to a high-pressure phase at 88 GPa after laser-heating at 1500 K within a diamond anvil cell. The new phase is highly incompressible, stiffer than shock-compressed sapphire and diamond above 170 GPa.
A study led by Zhu Maohttp://link.aps.org/doi/10.1103/PhysRevB.83.054114 (Stanford) suggests that oxide phases formed from earth garnets may have interesting properties at high pressures and are candidates for highly incompressible solids and many industrial applications. GGG is a material with good optical, mechanical, and thermal properties which make it promising for the fabrication of various optical components as well as substrate material for magneto-optical films and high-temperature superconductors [Z. Mao, Phys. Rev. Lett. 83, 054114 (2011)].