Terahertz Investigation of Cultural Heritage Synthetic Materials: A Case Study of Copper Silicate Pigments
Abstract
:1. Introduction
2. Materials and Methods
2.1. Terahertz Continuous Wave Spectroscopy (THz-CW)
2.2. Energy Dispersive X-Ray Fluorescence (ED-XRF)
2.3. Fiber Optics Reflectance Spectroscopy (FORS)
2.4. Pigments Samples
3. Results
3.1. Egyptian Blue
3.2. Han Blue
3.3. Han Purple
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
Abbreviations
THz-CW | Terahertz continuous wave |
ED-XRF | Energy Dispersive X-Ray Fluorescence |
FORS | Fiber Optics Reflectance Spectroscopy |
EB | Egyptian blue |
HB | Han Blue |
HP | Han Purple |
DFB | Distributed Feedback Lasers |
PCA | Photoconductive antenna |
PMs | Parabolic mirrors |
Vis | Visible |
SWIR | Short Wave Infrared |
NIR | Near-infrared |
FWHM | Full Width Half Maximum |
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Element | Counts | ||
---|---|---|---|
Si | K | 466.8 | 24.5 |
Ca | K | 13,525.2 | 155.5 |
Ti | K | 195.0 | 26.8 |
Fe | K | 688.7 | 37.2 |
Ni | K | 123.8 | 27.3 |
Cu | K | 187,378.9 | 435.0 |
Zn | K | 785.9 | 41.6 |
Sr | K | 162.7 | 23.5 |
Pb | L | 606.2 | 36.8 |
Element | Counts | ||
---|---|---|---|
Si | K | 362.1 | 22.4 |
Cu | K | 81,089.3 | 287.0 |
Zn | K | 283.2 | 29.9 |
Sr | K | 3972.71 | 94.1 |
Ba | K | 8993.3 | 107.0 |
Ba | L | 34,846.4 | 196.0 |
Pb | L | 390.1 | 35.8 |
Element | Counts | ||
---|---|---|---|
Si | K | 143.7 | 16.3 |
Ca | K | 251.0 | 41.6 |
Ti | K | 528.5 | 114.0 |
Fe | K | 87.4 | 18.9 |
Ni | K | 131.5 | 20.4 |
Cu | K | 54,558.9 | 236.0 |
Zn | K | 262.6 | 25.6 |
Sr | K | 3060.9 | 61.2 |
Ba | K | 7119.9 | 87.4 |
Ba | L | 21,309.6 | 178.0 |
Pb | L | 490.1 | 32.6 |
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Moffa, C.; Felici, A.C.; Petrarca, M. Terahertz Investigation of Cultural Heritage Synthetic Materials: A Case Study of Copper Silicate Pigments. Minerals 2025, 15, 490. https://doi.org/10.3390/min15050490
Moffa C, Felici AC, Petrarca M. Terahertz Investigation of Cultural Heritage Synthetic Materials: A Case Study of Copper Silicate Pigments. Minerals. 2025; 15(5):490. https://doi.org/10.3390/min15050490
Chicago/Turabian StyleMoffa, Candida, Anna Candida Felici, and Massimo Petrarca. 2025. "Terahertz Investigation of Cultural Heritage Synthetic Materials: A Case Study of Copper Silicate Pigments" Minerals 15, no. 5: 490. https://doi.org/10.3390/min15050490
APA StyleMoffa, C., Felici, A. C., & Petrarca, M. (2025). Terahertz Investigation of Cultural Heritage Synthetic Materials: A Case Study of Copper Silicate Pigments. Minerals, 15(5), 490. https://doi.org/10.3390/min15050490