Four Techniques To Examine A Painting

To detect anomalies beneath paintings

It doesnot directly detect the presence of metal nuclei

It must be confirmed by another technique

It gives an indication that there maybe is an under drawing

using polyene

polyene is oxidized over time

This causes their absorption to decrease

To examine the elemental composition from different colored areas

Involves irradiating samples with x-rays to excite element's inner electrons

Atoms emmit x-ray frequencies when de-excited

Can be detected for most metals and elements of atomic number 14 and larger

By spectrometer, full emission collected from any area of painting

Provides information from top 50 microns of painting's surface