This means that the spectrometer cannot detect sulfides such as those in vermilion and cadmium yellow pigments, and the microscope accessory cannot detect the oxides in zinc white and hematite. These pigments would normally be identified by X-ray diffraction. Common colors such as the beautiful deep azure called Prussian blue are readily detected by FTIR, even at low concentrations of the pigment, because there is no interfering absorption in this region of the IR spectrum. Such important pre-Hispanic objets d'art are, in a sense, the victims of their own excellence. Analytical science techniques offer the hope that we may at least understand how these amazing artistic statements were made before they are changed or destroyed.
Spectroscopic data are vital here.
These techniques investigate methods of recording, dating, treating, and managing the sites, as well as aspects of natural weathering. La Cueva de las Manos constitutes one of the first projects of its kind in Latin America. Artists and conservation scientists from North and South America are looking for ways to protect the sites. Their solutions will determine future policies on everything from how to manage visitor flow to raising public awareness of the fragility and cultural value of the petroglyph sites. Though the work has just begun, it is already uncovering surprises.