High-pressure, high-temperature experiment supports idea about gems’ origins
Y.N. Palyanov et al/PNAS 2013
Boundaries between tectonic plates may make ideal diamond nurseries, according to an experiment that mimics conditions deep in the Earth.
Diamonds form only at temperatures and pressures far greater than those on Earth's surface. Scientists have long thought diamonds could form in subduction zones, where one tectonic plate plunges under another and sinks hundreds of kilometers into the mantle.
To simulate this extreme environment, scientists led by Yuri Palyanov of the Russian Academy of Sciences in Novosibirsk put minerals that are common in Earth's crust into a chamber where the researchers could apply intense pressures and temperatures. The team found that at around 74,000 times atmospheric pressure and above 1,200° Celsius, diamonds crystallized.