Abstract

The ability to discriminate between objects manufactured from animal horn and chelonian (turtle, tortoise, or terrapin) shell is important from a cultural and archeological perspective such that it may allow conservators to determine the appropriate treatment and long-term care solution. It would also aid curators in identifying and cataloging items manufactured from these materials. Discrimination and classification is also a valuable tool for those involved in tracking the illegal trade in restricted materials of this nature. Attenuated total reflection infrared (ATR-IR) spectroscopy, using a single reflection diamond internal reflection element (IRE), coupled with discrimination analysis was used to analyze a total of thirty-nine samples (29 calibration samples, 10 validation samples). A discrimination analysis model was constructed using Mahalanobis distances to classify spectra into one of two classes. The model was then subsequently used to successfully classify all validation samples and correctly identify them as animal horn or chelonian shell based on second-derivative spectra of the amide I and II regions. This technique requires minimal to no sample preparation and may be used to nondestructively identify very small samples successfully without performing detailed secondary structural curve-fitting routines. This model should be a valuable resource to museums, conservators, and wildlife management programs for rapidly and reliably discriminating between animal horn and chelonian shell.

Attenuated total reflectance spectroscopy with chirped-pulse upconversion

Hideto Shirai, Constance Duchesne, Yuji Furutani, and Takao Fuji
Opt. Express 22(24) 29611-29616 (2014)

Use of attenuated total reflectance Fourier transform infrared spectroscopy to monitor the development of lipid aggregate structures

Mateo R. Hernandez, Elyse N. Towns, Terry C. Ng, Brian C. Walsh, Richard Osibanjo, Atul N. Parikh, and Donald P. Land
Appl. Opt. 51(15) 2842-2846 (2012)

Refractive indices of powdered materials using attenuated total reflectance spectroscopy

James B. Gillespie and George H. Goedecke
Appl. Opt. 28(18) 3985-3992 (1989)

Optimizing infrared spectral discrimination to enhance disease diagnostics: monitoring the signatures of inflammatory bowel diseases with anti-TNFα therapy

Hemendra Ghimire, Xinjie Hu, Gengsheng Qin, and A. G. Unil Perera
Biomed. Opt. Express 11(8) 4679-4694 (2020)

Enhanced photoluminescence spectroscopy for thin films using the attenuated total reflection method

Takashi Wakamatsu, Tadaaki Kitami, Tomoaki Maruyama, and Susumu Toyoshima
Appl. Opt. 50(5) 696-700 (2011)