• journal_title：European Journal of Mineralogy
• Contributor：Taijin Lu ; Hua Chen ; Zhili Qiu ; Jian Zhang ; Ran Wei ; Jie Ke ; Ichiro Sunagawa ; Richard Stern ; Thomas Stachel
• Publisher：E. Schweizerbart'sche Verlagsbuchhandlung Science Publishers
• Date：2012-
• Format：text/html
• Language：en
• Identifier：10.1127/0935-1221/2012/0024-2230
• journal_abbrev：Eur J Mineral
• issn：0935-1221
• volume：24
• issue：4
• firstpage：651
• section：Other Articles

Diamond crystals from the Shandong and Liaoning kimberlites, China, display a distinct “seed-like” multiple core growth structure with multi-stage growth history. Cathodoluminescence and DiamondView images revealed that the core portion of the diamonds is occupied by a “seed-like” precipitated or smaller core which could be a resorbed early crystal formed by a cuboid growth mechanism. At the boundary between the core portion and the octahedral layers, the nitrogen concentration drops abruptly to ~1 ppm from a few hundreds of ppm in the core portion, suggesting a fundamental change in geochemical growth environments in the mantle. This is associated with a switch in zoning trends in δ ¹³C from outward increasing to outward decreasing values, confirming that a change in growth conditions occurred.