Thai colour names used for mural paintings and Khon masks are not well known, uncommonly used, and some are forgotten. They are normally known today only among few artists who inherited the knowledge to paint them from their elders. However, the artists cannot quantitatively describe the characteristics of these colours, and this is a major impediment in colour identification and preservation studies that are necessary for future restoration works of temples and artifacts. The purpose of this article is to describe our research for identifying and quantitatively describing traditional Thai colours, as part of our effort to create a Thai Colour Name Dictionary. In this article, we show information about colour names which have never been mentioned in any international journal until now, and we describe the method we used to identify them with physical colours. The method is exemplified on 10 colour names. (c) 2011 Wiley Periodicals, Inc. Col Res Appl, 38, 229234, 2013.