________________
Vol-1, xxix
THE NEGLECTED ASPECTS OF....
105
characteristics and other aspects can be important for distinction and detection of naturally occurring pigments from artificially prepared which are generally used for faking and forgery.
Another technique useful for studying Paint layers and pigment particles is the cross-sectionls analysis, which helps to understand artist's technique.
For the purpose of safety and surety, it is necessary to cross-examine and confirm the microscopic observations by other scientific techniques, namely X-raydiffraction-powder-pattern analysis, spectro-graphic analysis, chromatographic analysis and other techniques.
For the precise detection and determination of pigments, small admixture and minor components occurring in a painting, it is essential to extract smallest quantity of sample from painting and such sample can be extracted by a needlepoint without causing harm to painting. Only technical experts know how to extract such micro samples for scientific examination without harming the painting proper.
X-rays are utilized for understanding the making of a work of art, and for revealing artist's material and artist's technique.
Painting can be scanned through x-rays16 for the purpose of knowing the existing invisible aspects. Each pigment has its own x-ray absorption"? capacity which depends on what pigment is made of. Heavy metal pigments, namely the lead white pigment and the zinc white pigment, can be detected in an x-ray. The X-ray fluorescence analysis and the x-ray diffraction-pattern analysis can determine 'some pigments in situ' on paintings. There is another technique known as X-ray diffraction power pattern analysis which can also be utilised for examination of artist's materials and artists Technique. This particular technique is based on the reflection of x-ray on the "Lattice of crystals”. A “Line-pattern", which is typical (and) characteristic for a particular pigment, “is produced by xrays on the photographic film and the identification of the x-ray diffraction powder pattern can be done by reference pattern from known pigments." The X-ray diffraction, the infra-red spectrometry, Raman micro-spectrometry are useful techniques, generally employed for structural investigations and examinations without harming paintings selected for structural probing.
