Squeeze shungite hard enough and it becomes diamond: 15 GPa, 1600 C, and you get nanopolycrystalline superhard material

The short version

A 2021 review from the Karelian Research Centre lists the industrial directions shungite research has taken. One of them stands out: put shungite carbon under enough pressure and heat and it converts straight into nanopolycrystalline diamond - the superhard material used for cutting and grinding tools.

The conditions

"наноструктурирования шунгитовых пород с образованием гиперфуллереновых углеродных структур" is one route the same group describes; the diamond route runs at roughly 15 GPa and 1600 °C. At those conditions the disordered shungite carbon reorganises into a dense diamond phase.

To put 15 GPa in perspective: that's about 150,000 times atmospheric pressure - the kind of squeeze you need because you're forcing two-billion-year-old graphene-stacked carbon to collapse into the diamond lattice.

Why it's worth knowing

Most carbon won't do this cleanly. Shungite's particular structure - graphene-like sheets and globules rather than random soot - makes it a workable feedstock for synthetic superhard materials. So the same rock sold for water jars is also, in a materials lab, a starting point for diamond.

(For shungite's other heavy-industry role - as a metallurgical reducing agent in cast iron, ferrochrome and ferrosilicon - see the metallurgical-flux thread on the forum. Same Karelian Research Centre review covers both.)

Sources

- Deines Yu.E. et al. (2021), "Шунгитовые породы Карелии: от геологических исследований к перспективам использования в инновационных технологиях", Труды Карельского научного центра РАН: cyberleninka.ru