It was collected in 2005 by Crick Smith UL - the University of Lincoln's specialist conservation and restoration consultancy division - using dental drills and scalpels, then mounted in resin for analysis.
Hundreds of such samples were collected from the Grade I-listed Victorian Gothic building on London's Euston Road, which was designed by Sir George Gilbert Scott and opened as the Midland Grand Hotel in 1873.
The building was converted into British Railways offices in 1935 but fell into disrepair in the 1980s after being declared a fire hazard.
Like the adjoining railway station, which reopened in 2007, St Pancras Chambers has undergone extensive renovation in recent years, with the paint samples providing vital information about its decorative history.
After the building was damaged by fire, Crick Smith UL was also able to help replace the ornate stencil designs on its ceilings and walls.
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