摘要
江苏省溧阳市南部小梅岭地区的梅岭玉 (软玉 )产于花岗岩和大理岩的外接触带中。通过野外地质调查、室内显微镜和扫描电子显微镜观察和分析、X射线粉晶衍射物相分析、电子探针成分分析和物理性质测定表明 :梅岭玉的主要矿物组成为透闪石 ,含有少量磁铁矿和粘土矿物 ,具纤维状变晶结构 ;梅岭玉中透闪石的主要化学组分为SiO2 、MgO、CaO ,次要组分Na2 O、P2 O5的含量明显高于和田玉中透闪石 ;玉石的颜色可分为白色、青白色和青色 ,随Fe2 +含量增加颜色加深 ,半透明至不透明 ,玻璃光泽 ,平均密度为 2 .99g/cm3,硬度 5～ 6 ,折射率 1.6 1(点测 )。梅岭玉的特殊内部结构使其块度较大、裂隙较少 。
Meiling jade (a natural nephrite), derived from Xiaomeiling region in Liyang, Jiangsu Province, occurs in the outer contact zone between granite and marble. Besides field geological investigation, the methods of microscope and SEM (scanning electron microscope) observation, X\|ray diffraction, electron microprobe analyses and determination of physical qualities are adopted for the study. The results show that the main mineral constituent is tremolite with nematoblastic texture, and a little magnetite and clay mineral. The main chemical components of tremolite are SiO 2, MgO and CaO, the minor components are Na 2O and P 2O 5, the contents of these components are higher than those in Hetian jade. Colors of Meiling jade are mostly white, grey\|white and grey, the colors become darker as the content of Fe 2+ increases. The jade is semitransparent or opaque, with vitreous luster, the average density is 2.99 g/cm 3, the hardness is 5～6, and the refraction index is 1.61. Due to special texture, Meiling jade with large pieces and few cracks shows a good technological processing property.
出处
《岩石矿物学杂志》
CAS
CSCD
北大核心
2002年第z1期99-104,共6页
Acta Petrologica et Mineralogica
基金
国家科技基础性工作专项资助项目 (2 0 0 1DEA10 0 0 8)
关键词
梅岭玉
软玉
透闪石
纤维状变晶结构
溧阳
江苏
Meiling jade
nephrite
tremolite
nematoblastic texture
Liyang
Jiangsu
