The process of skeletonisation depends on many factors, including the climatic, biological, anthropological and environmental factors surrounding the body. It occurs faster in a body present on the surface of ground than when buried. Tendons, ligaments, hairs and nails can sometimes be identifiable even after skeletonisation has occurred. It is expected that it takes around 5 years for bones to be completely free of soft tissue. Cartilages will decompose into a greasy material covering the articulating surfaces which when sawed would release smoke and smell of brunt organic matters.
Identification from bones are discussed in detail in ‘Guidelines on Forensic Identification of Skeletal Remains.’
Examination of the bone marrow space may reveal residual organic material that can sometimes be suitable for DNA analysis. Examination of the cut surface of a long bone under UV light may assist in dating, as there are changes in the pattern of fluorescence over time. Dating bones, as with all post-mortem dating, is fraught with difficulty.
Carbon-14 dating is believed to be of no use in this short time-scale, but examination of the bones for levels of strontium-90, which was released into the atmosphere in high levels only after the detonation of the nuclear bombs, may differentiate bones from before and after 1940’s.