Whenever I go to a new place, one of my favorite things to do is visiting museums. I love museums and I can spend days in museums (but also in bookstores) without ever getting bored. That’s because I love learning about the past and present cultures. I love imagining how people used to live in the past and what their lives were like based on the information we gather from the little we have left from them. For the same reasons, I also love archaeological sites, visiting old castles and ruins.
How can Science help the field of cultural heritage?
Most of the information we have about all these objects is gathered by using Science in one way or another. Here are four ways we can use Science in studying historical and art objects:
In order to find out the age of a certain object, we can use scientific dating methods that involve radioisotopes. Isotopes are variants of the same element, with the same number of protons in the nucleus, but different number of neutrons. Some of these isotopes are unstable, radioactive isotopes that, over time, decay into more stable elements. One of these radioisotopes that can be used for dating art objects is carbon-14 (number 14 tells us that there are 8 neutrons and 6 protons in the nucleus of this isotope). This is called radiocarbon dating. This element decays in time, a very long time—about 5730 years—to the more stable element nitrogen-14. Because we know this value, called the half-life, we can use radiocarbon dating to determine the age of objects that contain this isotope. This can be used for dating paintings, parchments, bones, and other objects that are made from organic matter.
Different environmental factors, such as humidity, temperature or certain chemical and biological factors, can lead to the deterioration of cultural heritage objects and sites. Using science, we can identify the best conservation conditions for different objects based on the chemical composition of the object. Knowing what the objects are made of, we can understand what kind of external factors are most likely to lead to their deterioration. Once we have this information, we can construct the ideal environment for each type of object. Thus, if we’re trying to conserve an object most prone to bacterial attack, we would keep the object in a chamber of inert gas to reduce the damaging effects of bacteria. If we know that humidity is the problem, which is often the case of wall paintings and mosaics, then we can try to ensure dry preservation conditions for those objects. By keeping these objects in their ideal environment, we can ensure their future conservation.
When the objects are in a poor state of conservation, we need to go a step further—sometimes we can try to restore the objects to their original state. In time, dust and other particles can accumulate on the surface of art objects, smoke and chemical reactions can lead to the discoloration of paintings and accumulation of patina on art objects made from metals, stone, or wood. The first step of the restoration involves the cleaning of the object—a chemical cleaning for paintings and laser cleaning for objects covered by patina. After cleaning a painting, an art restorer could try to repair the tears in paintings and eventually retouch the paint layer to return it to its original color. Extra care must be taken in the restoration process to ensure that the chemicals used for the cleaning and retouching are appropriate for that particular object. Any unwanted chemical reactions between the restoration materials and the art object can lead to bigger damages, and sometimes to the loss of art. This is why we need science in art restoration—to identify the correct materials we should use in restoring an art object.
Authentication of art
When it comes to authenticating art, there are many scientific methods that we can use, all of them providing different information that could hint at whether or not an object is authentic. We can use dating methods, which will give us information about the age of the object. However, this method is invasive and not ideal when we’re dealing with a very precious object. Museums wouldn’t be too happy about scientists requesting samples of their most expensive paintings to analyze regularly. Luckily, in the more recent year, the amount of sample needed for this method is minimal and that opened new possibilities for radioisotopic dating. Other scientific methods provide information about the chemical composition of the different materials and pigments that could also be used to authenticate art objects. In one of my past research projects, we were working on developing a method that uses mobile nuclear magnetic resonance to authenticate paintings. All these methods are valuable tools for authentication of art, but ideally, one would use a combination of the above-mentioned methods to assess the authenticity of art objects.