Infrared & Raman Users Group

IRUG is a community that encourages the sharing of high quality comparative reference spectral data.

We develop IR and Raman reference spectra for the study of works of art, architecture, and archaeological materials. Our database is peer-reviewed through a rigorous process facilitated by this website.

Anyone may search the database to view and print spectra. To access digital spectra and related information, you must join IRUG and contribute spectra. Click the button below to begin registration.


Featured Spectra

IRUG Statement on the War in Ukraine

The Board of Directors of IRUG, an international scientific and cultural heritage community, stands in solidarity with the people of Ukraine. We believe that science and cultural heritage flourish in a world where diverse cultures co-exist peacefully. We, therefore, condemn the Russian military invasion of Ukraine with its subsequent loss of precious life and destruction of cultural heritage. During and after this conflict, the IRUG Board will seek to support our members who have been impacted.

IRUG14 Virtual Conference, June 2021, Amersfoort, NL


The conference in honor of P. Andrew Lins (1945-2019) connected scientists, conservators, students & educators online to share infrared & Raman spectroscopic research for the study, documentation, & protection of the world’s cultural heritage.

IRUG14 took place from Wednesday, June 2 to Friday, June 4, 2021, during half-day sessions & featured 25 papers & 6 posters. Dr. John Delaney, the keynote speaker from the National Gallery of Art, Washington, DC, discussed standoff mid-infrared emissive imaging spectroscopy for mapping of artists’ materials in paintings. To view the complete speaker list & final program, click here: PROGRAM.

Registrants can watch the recorded presentations via the link provided previously. Further access & book of abstracts & posters are forthcoming. For inquiries, contact Suzan de Groot,

IRUG Extends Deep Gratitude to Our Conference Hosts:
  • Susan Lammers, RCE Director
  • Suzan de Groot, RCE Senior Scientist & Conference Organizer
  • Letty Spieker, RCE Communications
  • Inez van der Werf, RCE Senior Researcher & Conference Moderator
  • Thea van Oosten, RCE Senior Scientist, Retired & Conference Moderator

P. Andrew Lins (1945-2019): Remembering an Outstanding Colleague

IRUG pays tribute to the life of Andrew Lins, former chair of the Philadelphia Museum of Art, Conservation Department, who passed away on Christmas Day, 2019. Andrew was a highly accomplished conservator, scientist and renowned expert on metals and corrosion. His rich life and many accomplishments have been well-recognized. Less known is the importance of Andrew's early leadership that made possible IRUG's incorporation in the early 1990s. He firmly believed in the Group's mission of collaboration in the pursuit of accessible, high-quality reference data among institutions. Andrew was an unwavering advocate throughout IRUG's existence. His continued support greatly helped to propel IRUG on an international level. With fond memories, we always will be grateful for his guidance and friendship.

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