The technical analysis of the panel was carried out in order to identify the materials and techniques of the panel.  This helped to interpret the current appearance of the panel.  Techniques used were surface microscopy, cross section analysis, polarised light microscopy, x ray fluorescence, scanning electron microscopy, raman spectrophotometry and dendrochronology.  Fading of madder lake and indigo were identified, and the discolouration of copper based pigments.  The panel was found to be constructed of oak boards cut from a local source of trees to Cardiff.

The conservation and restoration of the panel involved the removal of surface dirt deposits, discoloured and opaque varnish coatings, old mismatched overpaint and the removal or re-shaping of irreversible fill material.  Structural conservation was minimally carried out.  

Bishop Marshall panel before treatment

Detail of angel’s robe after varnish removal showing mismatched overpaint.

Detail of angel’s robe after overpaint removal showing irreversible grey fill

Detail of angel’s robe after re-shaping the fill and retouching

Bishop Marshall panel after treatment

Plans for the re-display of the panel are in progress with a new mounting system being designed by the Cathedral Architect, March 2020.  It is hoped that the panel will be on display this year, 2020, as part of the Cathedral’s 700th anniversary, although the current lockdown situation with Covid-19 may preclude this.