关于翡翠研究中几个重要问题的思考   总被引：1，自引：0，他引：1  

周艳  刘嵘  曹姝旻 《岩石矿物学杂志》2009,28(1):87-92

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.  相似文献   

表生还原条件下翡翠水岩反应的热力学计算     

金春梅  丘志力  严若谷  李榴芬 《地质科学译丛》2009,(4):4-8

一些翡翠在表生还原条件下可观察到明显的水岩反应过程以及颜色与组织的改变。根据地质现象,从热力学计算的角度探讨了翡翠中的主矿物硬玉发生水岩反应后形成部分新的自生矿物的可能性。热力学计算的结果显示,在表生作用过程中,在环境存在额外的Mg2＋与Fe2＋的条件下,翡翠最易与Mg2＋和Fe2＋发生反应生成绿泥石。该结果为大多数无色翡翠经过表生还原作用后出现暗绿色-水绿色的颜色提供了一定的理论解释。  相似文献   

深圳翡翠市场的SWOT分析     

卜玥文  包德清 《地质科学译丛》2009,(2):51-54

深圳珠宝产业聚集区是中国内地最大的综合性珠宝首饰加工、制造与批发中心。近年来以万山工业区为中心逐渐形成翡翠批发市场,填补了深圳珠宝产业聚集区的空白。相对于广州、揭阳、平洲、四会等成熟翡翠市场来说,深圳翡翠市场仍属于一个新兴市场。对该翡翠市场进行了SWOT（即优势、劣势、机会与威胁）分析后认为,该市场的发展潜力巨大,但其竞争压力也十分严峻;同时,也为从业者正确认识该市场的环境态势、制定正确的经营策略、提高其竞争力、为深圳翡翠市场的健康、快速发展提供一定的指导。  相似文献   

Controls on the first appearance of jadeitic pyroxene, northern Diablo Range, California     

B. E. PATRICK  H. W. DAY 《Journal of Metamorphic Geology》1989,7(6):629-639

A reaction producing jadeitic pyroxene in metagreywackes of the northern Diablo Range has been identified on the basis of mineral distribution, isograd patterns and composition of coexisting minerals. The appearance of jadeitic pyroxene (∼Jd₈₀) is closely followed by the disappearance of pumpellyite, which indicates that pumpellyite plays a major role in the pyroxene-producing reaction. A new projection from hematite, lawsonite, chlorite, quartz and H₂O on to the NaAlO₂-FeO-MgO ternary confirms the role of pumpellyite in pyroxene production and suggests a reaction of the form: 1.00 pumpellyite + 0.31 chlorite + 8.71 albite + 0.70 hematite + 2.00 H₂O = 8.54 jadeite + 0.57 glaucophane + 3.09 lawsonite + 5.26 quartz. Metagreywackes of the northern Diablo Range were metamorphosed under conditions of P _H2O= P _total at 200-300 °C and 7.5-10.0 kbar. Despite the low temperatures attained during metamorphism, the assumption of equilibrium yields results consistent with field observations and phase relations.  相似文献   

"水墨画"种翡翠的矿物学特征研究          下载免费PDF全文

袁淼  欧阳秋眉  吴瑞华 《岩石矿物学杂志》2011,30(Z1):8-12

"水墨画"种翡翠是市场上出现的翡翠新品种,得名于其黑色不透明物质在无色的"地"上的不规则分布,形似水墨画。本文运用电子探针、X射线粉晶衍射、红外光谱等分析手段对"水墨画"种翡翠进行了研究,结果表明,"水墨画"种翡翠矿物组成以硬玉和绿辉石为主,含有少量的斜长石、磁铁矿及黑色不透明杂质。黑色杂质和磁铁矿为导致该种翡翠产生黑色和不透明的水墨画状外观的主要原因。  相似文献   

Hydrogen Incorporation in Crystalline Jadeite: Insight from First Principles Calculations     

ZHANG Xiaoling  FAN Xiaoyu  MENG Dawei  WU Xiuling  LIU Weiping 《《地质学报》英文版》2016,90(3):939-945

Hydrogen incorporation is critical for explaining defect energies, structure parameters and other physical characteristics of minerals and understanding mantle dynamics. This work analyzed the hydrogen complex defects in jadeite by the plane-wave pseudo-potential method based on density functional theory, and optimized the atomic positions and lattice constants in all configurations(different defective systems). Incorporation mechanisms considered for hydrogen(H) in jadeite include:(1) hydrogen incorporating with the O2 site oxygen and coexisting with M2 vacancy;(2) one H atom combined with an Al atom replacing Si in tetrahedron;(3) 4H atoms directly replacing Si in tetrahedron and(4) 3H atoms replacing Al on the M1 site. The four incorporation mechanisms mentioned above form the corresponding V_(Na)-H_i, Al_(Si)-H_i, V_(Si)-4H_i and V_(Al)-3H_i point defects. The molecular dynamics simulation to the ideal, V_(Na)-H_i, Al_(Si)-H_i, V_(Si)-4H_i and V_(Al)-3H_i point defects under the P-T conditions of 900 K, 2 GPa, the V_(Na)-H_i and Al_(Si)-H_i point defects under different pressures at T = 900 K, and Al_(Si)-H_i point defects under different temperatures at P = 3 GPa was performed to examine the preferential mode of hydrogen incorporation in jadeite by means of first-principles calculations. The calculations show that the averaged O–H bond-length in the hydrogen point defects system decreased in the order of Al_(Si)-H_i, V_(Na)-H_i, V_(Si)-4H_i and V_(Al)-3H_i. V_(Na)-H_i complex defects result in a contraction of the jadeite volume and the presence of Al_(Si)-H_i, V_(Si)-4H_i and V_(Al)-3H_i defects could increase the supercell volume, which is the most obvious in the V_(Al)-3H_i defects. The energy of formation of Al_(Si)-H_i and V_(Al)-3H_i complex defects was much lower than that of other defect systems. The V_(Al)-3H_i defects system has the lowest energy and the shortest O–H bond-length, suggesting that this system is the most favorable. The analytical results of vacancy formation energy, O–H bondlength, and the stability of the hydrogen defects in jadeite have suggested that the preferred hydration incorporation mode in jadeite is V_(Al)-3H_i complex defect.  相似文献   

硬玉塑性变形的AFM特征   总被引：2，自引：0，他引：2  

郭颖  赖兴运 《矿物学报》2003,23(2):158-162

利用原子力显微镜(AFM)对缅甸硬玉进行表面观察，研究其纳米级范围内矿物晶体的超显微结构及构造特征，探讨其形成的动态过程和物理化学等外部条件。结果发现在缅甸硬玉表面存在大量残余变形现象，尤其是以典型的扭折带、亚晶粒、晶粒扭曲结构为特征，反映了硬玉晶体内聚集了大量的位错。这些现象表明硬玉在其结晶之后曾在高压及较高温的地壳深处经历了强烈的塑性变形过程，它们与地表或近地表低温、低压条件下形成的以脆性破裂为主的变形方式有本质的差别。硬玉中大量的塑性变形现象表明了它是在比较复杂的动态地质环境中形成的，深部的这种复杂变形作用使得缅甸硬玉有别于世界上其它地方的硬玉，其独特的地质形成过程造就了本区为世界上典型的也是最大的翡翠矿床。  相似文献   

B货翡翠的红外光谱特征及鉴定意义   总被引：5，自引：0，他引：5  

陈炳辉  丘志力  王敏  龚盛玮 《矿物学报》2001,21(3):525-527

在对9个B货翡翠样品进行常规宝石学特征描述的基础上，进行了红外光谱测试。结果表明B货翡翠最主要的吸收峰是2959（或2966），2931（或2924）和2895cm^-1这一组，而1510，1581，1609cm^-1和3040，3060cm^-1这两组谱带可作为鉴定B货翡翠的辅助谱带，但不是必要的谱带。研究结果可为准确鉴定B货翡翠提供进一步的资料。  相似文献   

缅甸翡翠的光谱特征及呈色机理     

戴婕  孙传敏  解永顺  周瑞波 《四川地质学报》2007,27(4):296-300

从缅甸翡翠电子探针分析和紫外可见光吸收光谱、激光拉曼光谱、能谱、红外光谱等特征,探讨缅甸翡翠的呈色机理。主要对绿色翡翠和紫色翡翠的呈色机理进行研究。从硬玉呈色、次要矿物呈色和次生色分析得出,绿色翡翠主要由Cr3 致色,紫色翡翠可能是Mn2 致色。  相似文献   

Thermodynamics of mixing in diopside–jadeite,CaMgSi<Subscript>2</Subscript>O<Subscript>6</Subscript>–NaAlSi<Subscript>2</Subscript>O<Subscript>6</Subscript>, solid solution from static lattice energy calculations     

Victor L. Vinograd  Julian D. Gale  Björn Winkler 《Physics and Chemistry of Minerals》2007,34(10):713-725

Static lattice energy calculations (SLEC), based on empirical interatomic potentials, have been performed for a set of 800 different structures in a 2 × 2 × 4 supercell of C2/c diopside with compositions between diopside and jadeite, and with different states of order of the exchangeable Na/Ca and Mg/Al cations. Excess static energies of these structures have been cluster expanded in a basis set of 37 pair-interaction parameters. These parameters have been used to constrain Monte Carlo simulations of temperature-dependent properties in the range of 273–2,023 K and to calculate a temperature–composition phase diagram. The simulations predict the order–disorder transition in omphacite at 1,150 ± 20°C in good agreement with the experimental data of Carpenter (Mineral Petrol 78:433–440, 1981). The stronger ordering of Mg/Al within the M1 site than of Ca/Na in the M2 site is attributed to the shorter M1–M1 nearest-neighbor distance, and, consequently, the stronger ordering force. The comparison of the simulated relationship between the order parameters corresponding to M1 and M2 sites with the X-ray refinement data on natural omphacites (Boffa Ballaran et al. in Am Mineral 83:419–433, 1998) suggests that the cation ordering becomes kinetically ineffective at about 600°C.  相似文献