九龙璧玉石的特征及其开发利用

Gemology and Development of Jiulongbi Jade

九龙璧是产于闽西南地区的一种古老玉石．颜色以红、绿、白和黑四色为主．折射率为１．５３～１．６５，密度２．８～３．０，硬度５．８～６．８．抗折强度为４３～４８ＭＰａ，抗压强度为２５５．６４ＭＰａ．主要矿物成分为铁次透辉石、石英、钾长石等．它的颜色与其中所含的矿物种类不同有关．均匀细腻的结构使其具有较好的工艺性能．笔者根据九龙璧玉石的颜色和纹理，将其分为五个品种，并提出了开发利用的方向．

Jiulongbi is an ancient jade found in northwest Fujian. It has colours of red, green, white and black, RI 1.53～1.65, D 2.3～3.0, H 5.8～6.8, bending strength 43～48MPa and compression strength 255.64MPa.Jiulongbi jade consists mainly of Fe-diopside, quartz and K-feldspar. The colours are caused by different minerals in the jade. Green is related to Fe-diopside, red to K-feldspar and black to sime opaque minerals. Homogeneous and fine texture provides the jade excellent processing properties. The jades have been grouped into five classes on the basis of their colour and texture.