A computer simulation found a pentagon-shaped carbon molecule that would be as hard as diamond and could tolerate temperatures of almost 4000°C without breaking down
Source:
https://www.newscientist.com/article/2247671-newly-discovered-form-of-carbon-is-more-resilient-than-diamond/?utm_campaign=RSS%7CNSNS&utm_source=NSNS&utm_medium=RSS&utm_content=home