Lab-made hexagonal diamonds stiffer than natural diamonds

For the first time, researchers have hard evidence that human-made hexagonal diamonds are stiffer than cubic diamonds found in nature and often used in jewelry. Hexagonal diamonds have been found at some meteorite impact sites and others have been made in labs but were either too small or existed to briefly for measurement. Now scientists have created hexagonal diamonds large enough to measure their stiffness using sound waves.

from Latest Science News -- ScienceDaily https://www.sciencedaily.com/releases/2021/03/210331085856.htm