鉴定热处理琥珀的关键证据

在琥珀热处理实验研究的基础上,采用常规宝石学方法和红外光谱仪,测试并跟踪收集和对比分析了实验样品热处理前、后的宝石学参数和红外光谱的变化规律及琥珀内含物的演化、改造与破坏标识,并对获得的琥珀热处理效果进行了成因分析,从而总结出鉴定琥珀热处理的关键证据。研究结果表明：（1）折射率的增加、荧光的弱化或湮灭是热处理琥珀的重要佐证;（2）盘状裂隙、红色流纹、汽化纹、龟裂纹和氧化裂纹是热处理琥珀的重要标识;（3）FTIR光谱中I=2930cm-1/I=1735cm-1比值若≤1,可视为热处理琥珀的红外光谱指纹检测依据;（4）1735,1700cm-1处的羰基（C？O）伸缩振动与1260～1156cm-1处的C—O伸缩振动吸收强度的明显增强及多峰合并的趋势反映出热处理琥珀表面的热氧化反应;C？O浓度的增加可能是热处理琥珀红色的生色团,同时又是热处理琥珀荧光的淬灭剂。     

马鞍山绿松石中水的振动光谱表征及其意义

在室温和变温条件下对安徽马鞍山绿松石中水的结构特征进行红外吸收光谱和激光拉曼光谱分析研究,结果表明:绿松石中部分水分子与Cu2 结合成[Cu(H2O)4]2 水合离子,并在很大程度上制约了绿松石的颜色;马鞍山地区绿松石中结晶水的脱失温度约为303℃～310℃,结构水的脱失温度约为346℃～375℃。绿松石中H2O,OH-的振动是导致其水的激光拉曼光谱形成的主要原因,ν(OH)振动导致的强拉曼特征谱峰在3470 cm-1,3502 cm-1～3505 cm-1之间的弱谱峰则隶属3470 cm-1的次级谱峰,ν(H2O)的拉曼谱峰主峰位于3442 cm-1～3449 cm-1处。由ν(MFe,Cu-H2O)伸缩振动致平缓的拉曼谱峰主要分布在3074 cm-1～3303 cm-1附近。     

优质淡水珍珠的体色及其与拉曼光谱的关系

对不同颜色的优质淡水养殖珍珠进行激光拉曼光谱的研究,并试图从中找出珍珠颜色与其中的有机物以及和拉曼光谱的关系。结果发现,和纯白色系列优质珠相比,粉红色系列优质珠多了1134和1526 cm-1两个峰;紫色系列优质珠中的1017,1295,2231,2609 cm-1在纯白色珍珠和粉红色系列中均未曾出现;在有色珍珠中探测到某有机物的拉曼峰:由C—C伸缩振动引起的1121,1134 cm-1及C=C伸缩振动引起的1503,1526 cm-1,推测此有机物为聚乙炔类物质,不同于以前的研究者所认为的类胡萝卜素。不同色系的珍珠,其拉曼光谱有着明显的区别;随着同色系颜色的加深,有机物拉曼谱峰的强度也越来越强。     

褐帘石的谱学特征

本文研究了6个来自不同产状、不同地区的含褐帘石样品,包括4个伟晶岩(M1663来自内蒙集宁益元兴、M7673来自内蒙集宁察汗营地区、M4960来自美国Amherst County Virginia地区、M4976来自挪威Liksviken地区)、2个矽卡岩(M1697产自河北地区、M1679产自湖南郴县地区)。通过对这6个不同产状褐帘石的电子探针主量、稀土和微量元素分析及拉曼、红外光谱学的研究来揭示褐帘石晶体化学特征。结果表明,褐帘石成分均匀,晶体内发育微裂隙,局部有脉体充填,但不同产状的褐帘石样品在主量元素如Fe O、Ca O、Al_2O_3以及REE如Ce_2O_3、Nd_2O_3、La_2O_3的含量具有明显的差别。其系统的光谱学数据表明褐帘石晶体的特征峰强度和峰位的偏移均与其组分有关,并分析指派了部分光谱峰位的归属,揭示了褐帘石中特殊谱峰位置的迁移与其元素含量、晶体结构之间的关系。拉曼光谱揭示了褐帘石单晶有20组拉曼活性谱峰(ν1～ν20),其中ν2～ν4、ν5～ν8、ν16～ν19谱峰的迁移与A位上的Ca与稀土元素之间置换作用有关;ν10～ν12谱峰是O-Si-O弯曲振动引起,其拉曼谱峰的偏移可能与Si含量有关;ν13～ν14谱峰的迁移则可能是多种元素变化共同作用的结果。褐帘石单晶红外光谱展示了13组红外活性谱峰(a-m),h-k谱峰的偏移与在M1或M3位上Fe~(3+)和Al相互替代而导致的; b-g谱峰的偏移是与硅氧四面体中Si-O非对称伸缩振动有关; OH(l-m)双峰的出现可能与M1、M3位上Fe~(3+)的含量有关。研究结果表明伟晶岩类岩石中褐帘石晶体结构中Fe~(3+)与Al~(3+)间的置换作用强于矽卡岩类岩石中的褐帘石;而矽卡岩类岩石中褐帘石晶体结构中在A位上稀土元素与Ca置换作用则大于伟晶岩类岩石中的褐帘石。     

天然与合成紫晶的红外和偏振拉曼光谱鉴定特征

天然紫晶与合成紫晶的鉴别是国内外珠宝鉴定实验室的一个难题,前人主要从双晶、色带、包裹体、红外吸收光谱特征等方面开展了研究。在利用红外光谱鉴别天然紫晶与合成紫晶时,不同的学者尚对3595cm-1或3543cm-1吸收峰作为诊断性还是指示性的判据存在不同认识。本文系统采集了典型的天然紫晶与合成紫晶样品,研究了利用红外光谱测试技术鉴别天然紫晶与合成紫晶的局限性,并尝试将偏振拉曼光谱应用于紫晶成因鉴别。结果表明:利用3595cm-1、3543cm-1红外吸收峰进行紫晶鉴别仅具有指示性意义,不能作为决定性的判定依据,偏振拉曼光谱可作为重要的补充。天然紫晶的偏振拉曼光谱(偏振方向:HH)均出现400cm-1的拉曼峰,而该峰在合成紫晶偏振拉曼光谱中缺失;合成紫晶的偏振拉曼光谱(偏振方向:HH)均具有795cm-1、448cm-1的拉曼峰,而这两个峰在天然紫晶偏振拉曼光谱中缺失。偏振拉曼光谱产生差异的原因可能与天然紫晶和合成紫晶内部晶格变形程度的不同有关。本文揭示的400cm-1、448cm-1和795cm-1偏振拉曼峰可作为鉴别紫晶成因的新依据。     

氯盐溶液的拉曼光谱特征及测试探讨

常温下氯盐溶液水的拉曼包络线歪斜度受氯离子浓度和阳离子的影响,水拉曼包络线歪斜度很难准确评价复杂流体中的氯离子浓度,在-170℃下氯盐溶液的拉曼光谱研究表明,H2O和nCl-[H OH-]n的拉曼光谱峰能很好地分解并明显地显示,其中nCl-[H OH-]n的拉曼峰与H2O的拉曼峰比值与氯盐的浓度呈正相关,用nCl-[H OH-]n的拉曼特征峰强度(I3401～3413.18cm-1)与H2O的拉曼特征峰强度(I3088～3106cm-1)比值(InCl-[H -OH-]n/IH2O)为纵座标,作相关图,二者的相关性较好,可以应用于溶液中氯离子摩尔浓度测定。     

红外光谱和拉曼光谱在热处理海蓝宝石鉴定中的应用

在适当的热处理条件下,黄绿色绿柱石能够转变为理想颜色的海蓝宝石。天然海蓝宝石与热处理海蓝宝石的价格差异较大,因此探索热处理海蓝宝石的诊断性鉴定特征就显得十分必要。对不同温度下热处理海蓝宝石进行傅里叶变换红外光谱和激光拉曼光谱的测试分析,结果发现,当热处理温度超过400℃后,随着加热温度的升高,在红外光谱中由[Fe2（OH）4]2＋伸缩振动gI起的3233cm叫处吸收谱峰明显减弱,直至消失。5268cm叫附近由水伸缩和弯曲振动}I起合频区的吸收带由尖峰变得宽缓;8700,6818cm叫两处水吸收峰的相对强度也随着加热温度升高而减弱。热处理海蓝宝石Si-0-Si伸缩振动产生的在682,3604cm叫处的拉曼光谱谱峰强度随着加热温度升高逐渐减弱,1070cm“处的拉曼峰强度明显降低。经700℃加热后,拉曼光谱基线明显向上方漂移。这些光谱特征变化对热处理海蓝宝石的鉴定有重要意义。     

常见酸根离子浓度的激光拉曼光谱定量分析

探讨利用激光拉曼光谱法对微量包裹体溶液中常见酸根离子成分（氯离子、硫酸根和乙酸根）进行定量测量。依据酸溶液某些拉曼光谱参数（如拉曼强度、半高宽和谱峰面积等）与对应振动的分子或离子团数量有密切的定量关系，估算酸溶液中离子或分子的浓度。结果表明，硫酸和乙酸溶液的拉曼光谱特征峰参数与浓度呈良好的线性关系；电解质水溶液拉曼峰的形变参数WA1／WA2、WH1／WH2可用于估算氯离子浓度。运用多元统计学的方法，拟合出盐酸、硫酸和乙酸溶液的浓度与各拉曼参数的回归方程。     

沉积有机质的喇曼光谱研究

本文用激光喇曼光谱显微探针研究了选自广西、湖南和New Caldeonin（澳大利亚）的11个有代表性沉积变质岩样品中的沉积有机质。有机质有两个主要喇曼频率振动区域:1600cm-1峰和1350cm-1峰。文中对这两个特征喇曼谱峰的归属进行了说明,讨论了不同类型沉积有机质特征喇曼谱峰的差异和不同变质演化阶段有机质产生的喇曼光谱系统性变化规律,指出激光喇曼光谱显微探针技术是一种研究沉积有机质特征十分便利、有效的方法。     

锆石变生程度与放射性元素含量间的定量研究

为获得锆石变生程度与放射性元素质量分数之间的相互关系,对来自山东蒙阴金伯利岩中的锆石进行了阴极发光、激光拉曼光谱、离子探针测试和研究.研究表明,锆石样品的年龄近于一致;按照拉曼光谱特征峰1000cm-1左右的强度/半高宽比值和放射元素质量分数(wB)可以将锆石分为全晶质锆石、弱变生锆石、变生锆石、强变生锆石4类.放射元素总质量分数(wB)与拉曼光谱特征峰1000cm-1左右的强度/半高宽比值(H/W,设为r)之间符合经验关系方程:(1/r)1/2=1.3×10-2·(wB/10-6)1/2—0.11,可以借助锆石在1000cm-1左右的拉曼光谱特征峰值强度/半高宽比值并采用这一经验关系方程来大致计算出拉曼测试位置的放射性元素的质量分数.     

应用稳定同位素示踪琥珀的产地

利用稳定同位素比值质谱仪（IRMS）对波罗的海琥珀、多米尼加琥珀、墨西哥琥珀、缅甸琥珀及不同产地的柯巴树脂的13C,D,18O稳定同位素进行了高精度测定.研究结果表明：（1）不同产地琥珀的δ13C值分布在一个较为稳定的范围内,缅甸琥珀δ13C=-19.38‰～-22.90‰,平均值为-21.15‰;波罗的海琥珀δ13C=-22.76‰～-25.76‰,平均值为-24.35‰;多米尼加琥珀δ13C=-23.57‰～-26.63‰,平均值为-24.99‰,且均值无交叉;（2）不同产地琥珀的δ13C值与琥珀形成的地质时代存在较好的线性关系.具体表征为随着天然树脂石化地质年代（琥珀化程度）的增加,13C值有规律地增大,据此可推断不同产地琥珀成熟度由高到低的相对顺序为缅甸＞波罗的海＞多米尼加、墨西哥;（3）柯巴树脂的δ13C值为-26.82‰～-29.94‰,平均为-28.55‰,比琥珀的明显贫δ13C,依据实验测试统计数据,推荐参考临界值为-27.00‰（＋0.18,-3.00）,这为界定琥珀与柯巴树脂提供了稳定同位素依据;（4）缅甸琥珀δD=-195.90‰～-244.40‰,平均为-226.00‰;波罗的海琥珀δD=-235.90‰～-270.10‰,平均为-25δ.80‰;多米尼加琥珀δD=-202.80‰～239.40‰,平均为-219.90‰;墨西哥琥珀δD=-218.90‰.不同产地琥珀中δD的同位素变异反映了环境水（大气降水）与古纬度之间的变化规律,即随着琥珀产地古纬度的增加,δD逐渐减小;（5）不同产地琥珀在13C-18O,D-18O同位素之间及13C,D,18O同位素在二维图解、三维空间中具有很好的分区性,表明碳、氢、氧稳定同位素综合分析可以示踪琥珀的产地信息.     

http://www.sciencedirect.com/science/article/pii/S1674987115300050

The intense study of coleopteran inclusions from Spanish(Albian in age) and French(Albian-Santonian in age) Cretaceous ambers,both of Laurasian origin,has revealed that the majority of samples belong to the Polyphaga suborder and,in contrast to the case of the compression fossils,only one family of Archostemata,one of Adephaga,and no Myxophaga suborders are represented.A total of 30 families from Spain and 16 families from France have been identified(with almost twice bioinclusions identified in Spain than in France);13 of these families have their most ancient representatives within these ambers.A similar study had previously only been performed on Lebanese ambers(Barremian in age and Gondwanan in origin),recording 36 coleopteran families.Few lists of taxa were available for Myanmar(Burmese) amber(early Cenomanian in age and Laurasian in origin).Coleopteran families found in Cretaceous ambers share with their modern relatives mainly saproxylic and detritivorous habits in the larval or adult stages,rather than wood-boring behavior.Fifteen of the coleopteran families occur in both the Lebanese and Spanish ambers;while only five are present in both Spanish and French.Considering the paleogeographic proximity and similarity of age of the Spanish and French ambers,the small number of taxa found in common at both areas is surprising.The ancient origin for the Lebanese and Spanish ambers,the paleogeography(including some barriers for terrestrial biota) and the local paleohabitats are factors that may explain the dissimilarity with the French specimens.Wildfires are believed to be a more likely cause of resin production during the Cretaceous than infestation by beetles.Current knowledge of the beetle species found in the Cretaceous ambers is introduced.     

A look with μCT technology into a treasure trove of fossils: The first two fossils of the millipede order Siphoniulida discovered in Cretaceous Burmese amber (Myriapoda,Diplopoda)

Millipedes (Diplopoda) are an important fossil group of land arthropods in the Palaeozoic. However, there is a gap in the Mesozoic, with only slightly more than a dozen fossils being known, until the much more recent fossil records mainly from Cenozoic Dominican and Baltic ambers become available. Burmese amber, precisely dated to the Late Cretaceous, is known for an apparently rich but still undescribed millipede fauna, and might represent the ideal bridge to close this gap in the millipede fossil record. In addition, modern micro-computed tomography (μCT) technology allows complex 3D reconstructions of objects fossilized in amber. Here we utilize μCT technology to describe the first millipedes from Burmese amber, which are also the first two fossil representatives of the order Siphoniulida. Siphoniulida, with two known species and just nine recorded specimens, are the rarest and least known of the 16 extant orders of the Diplopoda. Records are known from Sumatra, Guatemala and Mexico. The two new fossils described here represent two distinct species, Siphoniulus muelleri sp. nov. and S. preciosus sp. nov., and indicate a wider distribution of this order in the Cretaceous. The holotype of S. muelleri sp. nov. was well-enough preserved so that characters of the head, such as the incisura lateralis, not investigated before in extant representatives of the order, could be studied. This study highlights the possibilities and challenges provided by μCT technology in investigating Diplopoda fossilized in amber.     

多米尼加与墨西哥蓝珀光致发光-拉曼光谱及微量元素赋存特征研究

蓝珀主要产于多米尼加共和国、墨西哥与缅甸,其形成机制、组成成分及光谱特征与之特定的产出地理环境有密切的关联.因此,蓝珀的产地研究成为当前珠宝玉石、考古及生物矿物学研究领域的热点课题.前人主要应用红外光谱、X射线荧光光谱、质谱、同位素示踪等技术开展了较系统的蓝珀产地的溯源研究,但限于蓝珀材质的类同,不同产地蓝珀的光谱学等...     

琥珀优化工艺实验研究

选用俄罗斯加里宁格勒琥珀原料为优化工艺实验研究对象,以市场上常见的琥珀品种为实验目标,通过控制实验过程中的温度、压力及环境气氛,获得了金珀、血珀、金花珀、红花珀及老蜜蜡等实验产品,并探讨了琥珀优化的工艺流程、工艺条件及影响因素。研究结果说明,琥珀优化的工艺流程分为准备阶段、装炉阶段、优化阶段和开炉阶段。通过净化工艺可获得金珀产品,通过烤色工艺可获得血珀产品,通过爆花工艺可获得花珀,在常压、长时间低温加热的缓慢氧化条件下可获得老蜜蜡。总结了影响琥珀优化工艺的因素,包括其原料的颜色、透明度、块度、温压条件、环境气氛等。     

缅甸琥珀内含物的初步研究及其意义

琥珀是中生代白垩纪至新生代第三纪松柏科植物的树脂经地质作用而形成的有机混合物.目前世界上琥珀产地主要有欧洲波罗的海沿岸国家,中美洲的多米尼加、墨西哥,亚洲中国抚顺、缅甸、日本久慈和盘城、泰国,大洋洲澳大利亚、新西兰哈密尔顿等.然而,具有商业价值的白垩纪琥珀目前只有缅甸产出.缅甸琥珀资源主要分布于缅甸克钦邦密支那到德乃(Tanai)一带的胡康盆地.本研究在缅甸琥珀中观察和发现共20只生物个体,属15种生物,均属于节肢动物门.其中大部分属于昆虫纲,包含了膜翅目的蜂科、双翅目的蚊科等,另有一些未确切鉴定的种类.     

A new twisted-wing parasitoid from mid-Cretaceous amber of Myanmar (Strepsiptera)

A second Mesozoic twisted-wing parasite (Strepsiptera) is described and figured based on an exceptionally well-preserved male in mid-Cretaceous (Cenomanian) amber from northern Myanmar. Phthanoxenos nervosus Engel and Huang, gen. et sp. nov., is distinguished from other strepsipteran lineages, particularly the contemporaneous Cretostylops engeli Grimaldi and Kathirithamby, also in Burmese amber, and Protoxenos janzeni Pohl et al. in mid-Eocene Baltic amber, and assigned to a new family, Phthanoxenidae Engel and Huang, fam. nov. Phthanoxenos exhibit features indicative of a more primitive phylogenetic position than Cretostylopidae but still more derived than Protoxenidae. Brief remarks are made on the geological history of the Strepsiptera.     

A golden age for ectoparasitoids of Embiodea: Cretaceous Sclerogibbidae (Hymenoptera,Chrysidoidea) from Kachin (Myanmar), Charentes (France) and Choshi (Japan) ambers

Sclerogibbid wasps are obligate parasitoids of webspinners (Embiodea). Both groups have a particularly scarce geological record and are known since the Cretaceous: there are only four species of webspinners known from Burmese amber, and only two sclerogibbids were described from Barremian Lebanese and Cenomanian Burmese ambers. Here we report transferred genus from Aptian Choshi (Japan) amber and new sclerogibbids from Cenomanian Burmese and Charentese (France) ambers. The taxa described from Burmese amber are: Burmasclerogibba aptera gen. et sp. nov., Cretosclerogibba gen. nov. (with C. antennalis sp. nov., C. contractocollis sp. nov., C. neli sp. nov. and C. rasnitsyni sp. nov.) and Edrossia vetusta gen. et sp. nov. The first European fossil sclerogibbid Gallosclerogibba alnensis gen. et sp. nov. is described from Charentese amber. The holotype of Chosia yamadai Fujiyama, from Choshi amber, is re-described; it appears to be the oldest Laurasian sclerogibbid. The significant abundance and variety of Burmese sclerogibbid wasps (60% of fossil species known worldwide), as proxy of their hosts, were probably caused by the protection granted to them by the silk webs and possibly by the limited predation from ornithuromorph birds or crown-group ants. While all three extant sclerogibbid genera have apterous females, genera with winged females (Cretosclerogibba and Edrossia) dominated in Burmese amber. Small silk galleries from hosts may have favored the preservation of wings in females of Cretaceous sclerogibbids. Most new species described in the present paper, in addition to C. yamadai, are characterized by a very slender neck and a very long frontal process concealing the antennal toruli. These characters disappeared in extant species. We suggest that this loss was caused by a change in the fauna of predators, penalizing species with long neck and rostrum.     

Hymenoptera (wasps,bees and ants) in mid-Cretaceous Burmese amber: A review of the fauna

The Burmese amber assemblage of Hymenoptera with its 47 constituent families is now the richest in Cretaceous. A collection of Burmite (Burmese amber) from the Hukawng Valley, Myanmar at the Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences was examined, revealing that Burmite inclusions contain a very highly diverse hymenopteran fauna with as many as ten families found new for the Burmese fossil assemblage. The mid-Cretaceous hymenopteran fauna of Burmese amber is revised at the family level. A high level of the first family occurrences and endemism is demonstrated suggestive of an insular syndrome affected the mid-Cretaceous Burmese biome, as well as somewhat contradictory features in composition of the hymenopteran families there.