1. The Artists:The Chemists: Rebecca CareyAmber Klein Melissa CofferShawn Leary Rick HamiltonRandall Short Patricia Lang Department of Chemistry, Ball State University

2. What gives rise to color in a molecule ? What sorts of artists’ pigments were used in ancient and medieval times? How can we determine molecular identity? How is the scientific method applied to a real-world problem?

3. Teleconferences with experts: Dr. Mary Virginia Orna Dr. Beth Price

4. Other special course activities: Made a modern synthetic pigment, Prussian Blue, and an egg tempera paint Sampling paints from the statue, microscopic examination of paints, collecting spectral data on the samples, and analyzing the spectra Trip to analytical laboratory in Noblesville to perform additional analysis Oral presentation to Peter Blume and Dr. Orna Collaborated on a written report

5. Why? (1) characterize artist & work (2) to determine if pigments consistent with the date (3) chronology of paint application (4) conservation Chemistry and Art

6. Circle of Hans Multscher German 1400-1467 Typical to be painted

7. Kreuztragender Christus -Created by Multscher in 1450

8. Tools Technique Pigments

9. Sample Collection A team effort!

10. Sample Locations Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 Sample 7

11. individual pigments, layering, texture, optical properties individual pigments, layering, texture, optical properties physical separation according to color sometimes possible physical separation according to color sometimes possible

12. How?

13. 3400 3300 1650 cm -1

14. ATR spectroscopy uses the phenomenon of total internal reflection. Molecular Analysis

16. K Electron energy level L Electron energy level M Electron energy level K α KβKβ eV 2.04.0 Elemental Analysis

17. 1b Sample 1B: White layer under blue, Bottom left cloak out side fold. White pigment on back of all samples

18. Sample Locations Sample 1 Sample 3

19. Sample 1 Location: Bottom left of cloak, outside of fold Description: Blue Sample 3 Location: Right side, bottom of cloak, inside of fold Description: Blue Microscopic Image

20. 3b Sample 3B: Blue Side Down, Right side bottom of cloak, inside fold Azurite: 2CuCO 3  Ca(OH) 2 Blue from Cloak

21. Sample 2 Location: Base, left side toward the back Description: Green Sample 4 Location: Base, right side toward the back Description: Green Microscopic Image

22. 2d Sample 2D: Green base left Green sample from base

23. Surprise!!!! Copper acetoarsenite

24. Sample 5 Location: Flat fold, left side of cloak Description: Rust, metallic, layered, fluorescent under UV light Pyrite? Microscopic Images

25. We’re no fool!! It is real gold and much more ! Red Ochre: Fe 2 O 3 Red Ochre has been used since prehistoric times. It can be found in volcanic regions or can be produced by heating yellow ochre.

26. 4a Reference spectrum of hide glue Glazy part of paint

27. Sample 6 Location: Book binding Description: Red, dull Microscopic Images

28. Sample 7 Location: Bottom of cloak, left side Description: Fiber

29. 7c Sample 7C: Fiber White end, Bottom of cloak

30. Blue cloak: Azurite Clay Calcium Carbonate Green base: Protein/Copper acetoarsenite Not determined Calcium carbonate Outer Cloak Gold Red Ochre/clay/gypsum Calcium carbonate Protein Red book binding: Red Ochre/clay/gypsum Calcium carbonate Protein

32. -Mr. Peter Blume, Director of the Ball State Art Museum -Bob Galyen, TAWAS -Ball State Office of the Provost--BSU Teleplex -Michael Kutis, Geology Technician at Ball State --Beth Price, Senior Conservation Scientist, Philadelphia Museum of Art -Dr. Mary Virginia Orna, Scientist-in-Residence, College of New Rochelle