Recent research: Caught in the act: Diamond growth and destruction in the continental lithosphere

Click Me

Our recent article published in the journal GEOLOGY presented CT scanning 3D models. Click the button above to read the full article.

Diamonds preserved in eclogite xenoliths—fragments of deep lithospheric mantle carried to the surface by kimberlites—offer a rare glimpse into diamond formation in their native rock. In this groundbreaking study, the authors used high-resolution X-ray computed tomography to observe diamond morphologies inside 24 such xenoliths in unprecedented detail.

Key findings include:

• Evident Growth within the Mantle: Many diamonds retained their classic, sharp, step-faced octahedral shapes—even at the xenolith surface—indicating that kimberlite magma did not significantly erode them.

• Signs of In Situ Destruction: Some xenoliths contained only rounded, irregular diamonds, suggesting that aggressive melts or fluids resorbed them before they were transported by kimberlites.

• Snapshots of Complex Histories: A few xenoliths show both intact octahedral diamonds and resorbed, rounded ones—evidence of multiple events in the mantle, some diamond-friendly and others hostile.

These “caught in the act” samples provide a clear picture of diamond growth, preservation, and destruction processes occurring within the subcontinental lithospheric mantle—long before the dramatic kimberlite eruptions carried them skyward.