钴蓝颜料（Smalt）在故宫建福宫彩画中的发现

钴蓝颜料（Smalt）是一种产自欧洲的进口蓝色颜料，是一种经过研磨的钴玻璃粉末，从十五世纪中叶开始广泛用于欧洲油画与壁画中。在故宫的建福宫中发现有这种钴蓝颜料（Smalt）。但在明清文献中，钴蓝颜料（Smalt）尚无明确记载。本文主要对始建于乾隆七年（公元1742年）的建福宫内檐脊枋彩画进行了调查和采样，采用显微镜分析和显微激光拉曼光谱分析蓝色颜料的种类和彩画结构，特别是钴蓝颜料（Smalt）使用的时代和分布进行了认真的研究。分析结果表明：建福宫建造时，靛蓝是一种经常使用的蓝色颜料，故宫建福宫钴蓝（Smalt）颜料的使用时代晚于建筑的建成年代（公元1742年），而且一般与颗粒大小接近的石青混用。

The Discovery of Smalt in Jianfu Palace in Forbidden City

As a type of external pigments, smalt was discovered in some wall or wood painting in China since the end of last century. Most of those sites with smah painting are royal palaces or religious buildings. But it is sill uncertain when smalt came to China and was one of popular blue pigments in Chinese significant buildings. Recently, we began to study the paintings （Caihua） in Jianfu Palace buih in 1742 AD. By means of Microscopy, Scanning Electronic Micorcopy and Raman Microscopy we found indigo was the earliest blue pigments in the palace. Then the mixture of azurite and smah took the place subsequently. With the assistance of history documents, we deduced that smah may not be used in Chinese imperial buildings until middle period of Qing Dynasty （1755-1775 AD）. And it was quite popular to mix azurite with smait for blue painting in Forbidden City.