C2/m丁道衡矿-(Ce)的发现与研究

The Discovery and Study of C2/m Dingdaohengite-(Ce) from Panzhihua V-Ti-Fe Mines, China

丁道衡矿-(Ce)是在白云鄂博REE-Nb-Fe矿发现的一种新的稀土元素矿物,被视为是真正的珀硅铈钛矿(Perrierite)的同质多象体和硅钛铈矿(Chevkinite)亚族C(1)位上的钛类似物。同时,它还是自然界发现的首例硅钛铈矿亚族具P21/a空间群的天然产物。之后,在攀枝花V-Ti-Fe矿红格矿区找到一种几可全方位同白云鄂博产原型丁道衡矿-(Ce)对比,但空间群为C2/m的丁道衡矿-(Ce)变体,并作了全面、系统的矿物学研究。自此,参照先例,攀枝花产具C2/m空间群的丁道衡矿-(Ce)宜称C2/m丁道衡矿-(Ce);而白云鄂博原型丁道衡矿-(Ce)宜称P21/a丁道衡矿-(Ce)。C2/m丁道衡矿-(Ce)的发现与研究揭示,已有的硅钛铈族矿物何以具有C2/m变体和P21/a变体的成因解释,尚不能圆满诠释2种变体的形成。

Dingdaohengite-（Ce） is a new rare-earth element mineral species from the Bayun Obo REE-Nb-Fe Mine, Inner Mongolia, China. The mineral should be regarded as both a Ti-analogue at the C（1） site of chevkinite-（Ce） subgroup and a ture polymorph of perrierite-（Ce）. At the same time, it is the first example for the chevkinite-（Ce） subgroup with P2l/a space group in nature, too. Later, dingdaohengite-（Ce） with C2/m space group from the Panzhihua V-Ti-Fe Mines was discovered. Except space group, there is a close parallel in physical and chemical features between the two modifications. To be precise, it is suggested that dingdaohengite-（Ce） with P2ja space group is favourably refered as P2Ja dingdaohengite-（Ce）, Similarly, dingdaohengite-（Ce） with C2/m space group as C2/m dingdaohengite-（Ce）. The discovery and study of C2/m dingdaohengite-（Ce） reveal that the available genetic explanations, for the question that why there are two different interior symmetry to the chevkinite subgroup, can not illuminate the origin of the two space groups.