关于翡翠研究中几个重要问题的思考

A preliminary discussion on some important problems in jadeite research

随着与翡翠伴生或共生的过渡品种的不断出现,翡翠成因研究和人工合成技术开发面临着新的挑战和契机。首先,现行的行业性翡翠命名标准已显得过于笼统,难以区分传统观念中的翡翠及其过渡种属,妨碍了市场的良性发展。此外,越来越多的研究表明,在高压俯冲带内,传统观念中的翡翠及其伴生岩石,如钠铬辉石岩(玉)、绿辉石岩(玉)、钙铝榴辉岩等一些高压岩石之间存在时间和空间上的关联性。笔者认为俯冲带中形成的深部熔体与超基性岩之间的交代变质是导致岩石分带和岩性多样化的根本原因,提出了俯冲带熔体交代成因说,认为俯冲带、深部流体和超基性岩体是形成翡翠及其过渡品种的3个必要条件,并因此指出在人工合成过程中引入流体相很可能是降低实验条件的苛刻程度、从而合成出真正具有商业意义的翡翠的途径。

With the continuous appearance of jades associated with jadeite, the researches on the genesis and synthetic technology of jadeite are facing new challenges and opportunities. The existing National Standard of Jadeite Nomenclature has become too broad, and it is difficult to distinguish jadeite in the traditional concept from its transitional species, which would hinder the healthy development of the market. In addition, more and more studies show that in the subduction zone of high pressure, jadeite is spatially and temporally related to other high-pressure rocks such as ureyitite （jade）, omphacitite （jade） and groeclogite. The authors believe that the diversification of rock zonation and lithology of these high pressure rocks can be attributed to the metasomatism that took place between deep melt and ultrabasic rocks in the subduction zone, and thus propose a hypothesis of subduction melt metasomatism to explain jadeite formation. It is held that the subduction zone, deep melt and ultrabasie rocks constitute three necessary conditions for the formation of jadeite and its transitional varieties. It is also thought that the introduction of fluid phase in the synthesizing process can possibly alleviate the harsh conditions of high temperature and high pressure reaction and hence realize the successful synthesis of commercial jadeite.