Department of Mineral Sciences, Natural History Museum of Los Angeles County, Los Angeles, CA 90007, USA.
Microsc Microanal. 2012 Dec;18(6):1292-302. doi: 10.1017/S1431927612013542. Epub 2012 Dec 10.
The 49 type I natural pink diamonds examined exhibit color restricted to lamellae or bands oriented along {111} that are created by plastic deformation. Pink diamonds fall into two groups: (1) diamonds from Argyle in Australia and Santa Elena in Venezuela are heavily strained throughout and exhibit pink bands alternating with colorless areas, and (2) diamonds from other localities have strain localized near the discrete pink lamellae. Growth zones are highlighted by a blue cathodoluminescence (CL) and crosscut by the pink lamellae that emit yellowish-green CL that originates from the H3 center. This center probably forms by the recombination of nitrogen-related centers (A-aggregates) and vacancies mobilized by natural annealing in the Earth's mantle. Twinning is the most likely mechanism through which plastic deformation is accommodated for the two groups of diamonds. The plastic deformation creates new centers visible through spectroscopic methods, including the one responsible for the pink color, which remains unidentified. The differences in the plastic deformation features, and resulting CL properties, for the two groups might correlate to the particular geologic conditions under which the diamonds formed; those from Argyle and Santa Elena are deposits located within Proterozoic cratons, whereas most diamonds originate from Archean cratons.
经检验的 49 颗 I 型天然粉色钻石的颜色仅局限于在{111}方向上取向的薄片或条带中，这些颜色是由塑性变形产生的。粉色钻石可分为两类：（1）来自澳大利亚阿盖尔矿和委内瑞拉圣埃琳娜矿的钻石在整个晶体中受到强烈的应变作用，呈现出粉红色条带与无色区域交替出现的特征；（2）来自其他产地的钻石则将应变局限在离散的粉色薄片附近。生长带通过蓝色阴极发光（CL）突出显示，并被粉色薄片交叉切割，这些薄片发出的黄绿色 CL 源自 H3 中心。这个中心可能是由氮相关中心（A 聚集体）和在地球地幔中自然退火时移动的空位重组形成的。孪晶是这两组钻石适应塑性变形的最可能机制。塑性变形通过光谱方法产生了新的可见中心，包括负责粉色的中心，但仍未被确定。两组钻石的塑性变形特征和由此产生的 CL 特性的差异可能与钻石形成的特定地质条件有关；来自阿盖尔和圣埃琳娜的钻石是位于元古代克拉通内的矿床，而大多数钻石则来自太古代克拉通。
