The colours of metals have attracted the attention of humanity since ancient times, and coloured metals, in particular gold compounds, have been employed for tools and objects symbolizing the aesthetics of power. In this work, we develop a comprehensive framework to obtain the reflectivity and colour of metals, and show that the trends in optical properties and the colours can be predicted by straightforward first-principles techniques based on standard approximations. We apply this to predict reflectivity and colour of several elemental metals and of different types of metallic compounds (intermetallics, solid solutions and heterogeneous alloys), considering mainly binary alloys based on noble metals. We validate the numerical approach through an extensive comparison with experimental data and the photorealistic rendering of known coloured metals.

金属的颜色自古以来就吸引了人类的注意力，有色金属，尤其是金化合物，已被用作象征权力美学的工具和物品。在这项工作中，我们开发了一个全面的框架来获取金属的反射率和颜色，并表明可以通过基于标准近似的直接第一原理技术来预测光学特性和颜色的趋势。我们将其用于预测几种元素金属和不同类型的金属化合物（金属间化合物，固溶体和非均质合金）的反射率和颜色，主要考虑基于贵金属的二元合金。我们通过与实验数据和已知有色金属的真实感渲染进行广泛的比较来验证数值方法。