Abstract Zwischgold, or part gold, is a bi-layered metal foil made from gold and silver, popular in European sculptures from the 14th century. It is notoriously difficult to unambiguously identify and to study in detail, due to its close appearance to gold leaf (when still well preserved) and complicated individual situations. Although Zwischgold is nowadays commonly viewed as an economical substitute for gold leaf, arguments regarding its function have circulated for decades. In order to understand the application and related functions of Zwischgold in late medieval sculptures, a survey of 162 objects was recently implemented at the Swiss National Museum Collection Centre, focusing on polychrome wooden sculptures mainly dated 1400–1550 and produced in southern Germany and Switzerland. Handheld X-ray fluorescence (XRF) measurements show a high rate of correlated silver and gold signals mainly in a proportion range of 1:5–3:1, indicating Zwischgold in extremely diverse areas such as hair, beard, crown, gown fold, bordure, dalmatic, undergarment and attribute of saint statues, as well as altar background, frame and framework. This non-invasive XRF analysis is a first step to efficiently locate Zwischgold applied areas and obtain basic statistics regarding the Zwischgold applied artefacts. It provides objective evidence showing that the reasons for medieval Zwischgold application are not limited to cost-saving, but include other factors such aesthetics, symbolism, workshop preference and workability. We discuss such factors with some illustrative case studies, in which visual light microscope (VLM) and scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX) measurements on samples exhibit certain technological features of Zwischgold of that epoch, including its foil structure, thickness and materials compositions.

中文翻译：

---

从瑞士国家博物馆中世纪晚期彩色雕塑的多分析调查中对 Zwischgold 应用的新见解

摘要 Zwischgold，或称部分金，是一种由金和银制成的双层金属箔，在 14 世纪的欧洲雕塑中很受欢迎。众所周知，由于其外观与金箔相近（当仍保存完好时）且个体情况复杂，因此很难明确识别和详细研究。尽管 Zwischgold 现在通常被视为金箔的经济替代品，但关于其功能的争论已经流传了几十年。为了了解 Zwischgold 在中世纪晚期雕塑中的应用和相关功能，瑞士国家博物馆收藏中心最近对 162 件物品进行了调查，重点调查了主要年代为 1400-1550 年、产于德国南部和瑞士的彩色木雕。手持式 X 射线荧光 (XRF) 测量显示相关银和金信号的比率很高，主要比例范围为 1:5-3:1，表明 Zwischgold 存在于极其多样化的区域，例如头发、胡须、皇冠、礼服褶皱、圣像的边框、达尔马提克、内衣和属性，以及祭坛背景、框架和框架。这种非侵入性 XRF 分析是有效定位 Zwischgold 应用区域并获得有关 Zwischgold 应用人工制品的基本统计数据的第一步。它提供的客观证据表明，中世纪 Zwischgold 应用的原因不仅限于节省成本，还包括其他因素，如美学、象征意义、作坊偏好和可操作性。我们通过一些说明性案例研究讨论这些因素，