Geologists say they have discovered deposits in Antarctica of the igneous rock that yields diamonds.
Writing in the journal, Nature Communications, an Australian team reports finding kimberlite in the Prince Charles Mountains of eastern Antarctica.
Diamonds are formed from pure carbon under extreme heat and pressure at depths of about 150km in the Earth's crust.
Volcanic eruptions bring the crystals to the surface, usually preserved in another type of bluish rock called kimberlite.
The BBC reports the presence of kimberlite has been a clue to significant deposits of diamonds in other parts of the world, including Africa, Siberia and Australia.
Under an international treaty, mining activity is prohibited across the continent. However, the Protocol on Environmental Protection to the Antarctic Treaty is up for review in 2041 and could be subject to change.