Portable Raman Spectroscopy for Art & Archaeology Applications

Importance of the Topic

Portable Raman spectroscopy has become an indispensable tool in art and archaeology for its ability to provide detailed molecular information without harming priceless artifacts. By combining fiber-optic probes with non-destructive, non-contact analysis, conservators and researchers can examine pigments, binders, corrosion products, and degradation processes directly on site. This capability preserves cultural heritage while delivering rapid, accurate data that guide restoration and authenticate artworks.

Objectives and Study Overview

This whitepaper presents a field-ready Raman solution designed to address challenges faced by conservationists and archaeologists. The primary goals are:

• To demonstrate how portable Raman systems enable in-situ identification of organic and inorganic compounds on artworks and archaeological finds.
• To highlight the system’s flexibility across diverse substrates—painted surfaces, ceramics, statues, wall murals, tapestries and environmental patinas.
• To showcase practical workflow elements, from handheld operation to tripod-mounted video microscopy.

Methodology and Instrumentation

The described approach leverages a lightweight, rugged Raman spectrometer connected to a fiber-optic probe. Laser excitation wavelengths (532 nm or 785 nm) are selected based on sample fluorescence. Real-time spectra are collected without sample removal, enabling immediate analysis. A detachable microscope head and tripod adapter facilitate remote measurements in confined or elevated locations.

Used Instrumentation

• i-Raman Plus 785/532 S and i-Raman Prime spectrometers (spectral range down to 65 cm⁻¹)
• Battery pack for extended field operation
• Video microscope with detachable camera head (BAC151B)
• Tripod and adaptor for remote sampling
• BWID identification software with pigment, dye, mineral and inorganic libraries
• Optional quantitative analysis packages: BWIQ and Vision

Main Results and Discussion

Field deployments of the i-Raman series have demonstrated:

• Adjustable laser power down to 1% to protect sensitive samples
• High-quality Raman spectra from a range of substrates under ambient conditions
• Successful discrimination of pigments, organic binders and corrosion layers
• Efficient mapping of degradation phenomena such as oxidation and biological growth

The integration of video microscopy permits visual targeting of micro-areas, improving data relevance and reproducibility.

Benefits and Practical Applications

Key advantages of this portable Raman solution include:

• Non-destructive, non-invasive analysis preservation of original surfaces
• On-site flexibility—no sample transport or preparation required
• Rapid identification of materials to inform conservation strategies
• Authentication support through comparison with spectral libraries
• Ability to monitor environmental effects and material degradation over time

Future Trends and Opportunities

Emerging directions for portable Raman in art and archaeology encompass:

• Integration with artificial intelligence and machine learning for automated spectral interpretation
• Miniaturization of spectrometers for even greater field portability
• Expansion of spectral libraries to cover a wider range of historical pigments and binders
• Wireless data transmission and cloud-based collaboration among conservation teams
• Multimodal imaging combining Raman with hyperspectral or X-ray fluorescence techniques

Conclusion

Portable Raman spectroscopy offers a versatile, high-performance approach for in-situ analysis of cultural heritage materials. Its non-destructive nature, coupled with advanced software libraries and field-ready design, empowers conservators and archaeologists to make informed decisions on preservation, authentication and research without compromising artifact integrity.