广元千佛崖莲花洞彩绘颜料拉曼光谱分析

为了解广元千佛崖莲花洞造像的制作工艺与彩绘颜料成分,利用体视显微分析、金相显微分析、激光拉曼光谱分析技术对其进行物相和成分分析。分析结果表明,莲花洞造像彩绘直接绘制在岩石雕像表面,无底层。彩绘颜料分为多层,最多有三层,说明历史上至少有两次重绘。红色颜料为赤铁矿、朱砂;蓝色颜料主要为青金石与石青;绿色颜料为石绿、碱式氯化铜;白色颜料为硫酸铅。同时也表明,拉曼光谱分析彩绘颜料成分组成简便、快速、对样品要求量小,对样品无损分析,符合文物材质分析的要求,并可得到准确的信息。造像彩绘制作材料及工艺的分析结果为莲花洞造像彩绘保护研究提供了科学依据。

Pigment analysis of Lotus Cave statues using Raman spectroscopy and microscopy

In order to elucidate the pigment compositions and technologies used for the painted statues in the Lotus Cave of the Thousand-Buddha Cliff in Guangyuan, we conducted phase and component analyses using stereomicroscopy, metallographic microscopy and Raman spectroscopy. The analyses show that pigments of the Lotus Cave statues were applied directly to stone surfaces without a preparation layer. The statues have multiple layers (up to at least three layers) of pigments, which indicate that the statues had been repainted at least twice in the past. The red pigment is made from hematite and cinnabar, the blue pigment from lazurite and azurite, the green pigment from malachite and atacamite, and the white pigment from anglesite. Raman spectroscopy is particularly useful for pigment analysis due to its high accuracy and requirement for very small samples, making it almost non-destructive. The results obtained on painting materials and technologies from the Lotus Cave statues provide scientific evidence for related conservation research.