If a work of art cannot be detected as a forgery at first glance, scientific or forensic tests can be done to determine its authenticity.
Scientific tests allow an examination of all the contents of a painting, including its chemical composition, the age of the canvas or panel, the chemical structure of the paint used, and the ingredients used to bind the painting.
There are two categories of scientific tests.
The first includes technical photographs that use X-ray, infrared, and ultraviolet light. Infrared reflectography identifies marks or lines that lie beneath the surface of the painting. X-ray photography utilizes short wave radiation to detect alterations in the painting. It can also indicate the types of paint the work contains or identify areas of the painting that have been repaired or changed. For example, X-rays can reveal a forged signature added after the initial painting was finished.
The second category, and the most effective, refers to the extraction and analysis of paint samples. The most effective method is fluorescence spectrometry through X-ray reflection. In this method, certain characteristics of the pigments can help assign a probable date to the painting.
There are other pigment analysis techniques that are invasive because they require small samples of paint.
Other scientific tests are carbon-14 dating, DNA analysis of organic material used in the artwork, and dendrochronology (the scientific study of wood dating through the rings of tree trunks), which allows us to determine the age of the supports.
Forensic investigation, on the other hand, tracks a work utilizing various elements including the following: existing documentation; the dimensions of the painting; digital fingerprints in the paint; labels, markings, or writing on the back or the front; the study of the signature; where and when the canvas or support panel was made; and information about the paint, brushes, or varnishes used.
By combining the scientific and forensic tests previously described with Morellian Analysis, we can reach an exact evaluation of the authenticity of a painting. Forensic investigation can determine the age, origin, composition, and materials of a work of art, while Morellian analysis evaluates the stylistic details of a painting and which studio it can be attributed to.