Hair is their past

Non-destructive Raman spectroscopy may reveal lifestyles of historic figures.

Researchers at Bradford University, UK, have analysed preserved historical hair samples dating from around 300 years ago. The group’s earlier work on human hair obtained from burial sites led to hair samples, which belonged to Robert Stephenson and Sir Isaac Newton, being donated from private collections and museum archives.

Acquiring these specimens has enabled Howell Edwards’ team to make a comparison of the condition of modern hair samples, archaeological samples from burial sites, and historical samples subjected to conservation.

Since no destructive pre-treatment is required, and a low powered laser is used, Raman spectroscopy has been employed as an ideal method for the initial screening of molecular contaminants on the hair shaft’s surface. Since only a single strand of Newton’s hair was available for analysis it was vital that a non-destructive technique was used.

Although these valuable samples were observed to be in remarkably good condition considering their age, the preserved hair was noticeably more degraded, possibly because bacterial or fungal attack was exacerbated by the storage method for the hair. Raman spectroscopy complements the destructive methods which are also needed to gather further information from the sample and perhaps allow an insight into these historical figure’s lifestyles. Edwards anticipates that once the technique is established it could lead to the development of a database that holds forensic information about historically important samples from museums.

Carolyn Ackers