This lesson focuses on the identification of vermilion (mercury sulfide) using XRF spectroscopy. Vermilion, a historically significant red pigment, is characterized by its mercury content and was widely used in art before being replaced by cadmium red due to toxicity concerns.
Objectives
- Understand the spectral characteristics of vermilion, including its L Alpha, L Beta, and L Gamma lines.
- Recognize the role of lead in pigment layering and ground preparations.
Materials
- Reference materials with pure vermilion from Pigments Checker STANDARD.
Lesson Plan
- Introduction to Vermilion: Discuss its historical significance and chemical composition (mercury sulfide). Highlight its transition from a primary pigment to being replaced by cadmium red.
- Spectral Analysis: Examine the XRF spectrum of vermilion, focusing on the L Alpha, L Beta, and L Gamma lines.
- Practical Application: Analyze XRF spectra from artwork samples, such as a painting with red drapery, to confirm the presence of vermilion. Compare these results with spectra of pure vermilion.
- Lead Identification: Identify lead peaks in the spectra, often associated with lead white in ground preparations or mixed pigments.
