Graffiti cleaning renaissance funerary monuments at St Mary’s Church Graveyard, Kilkenny.
Non abrasive cleaning using alkaline gels compatible with limestone and selective steam cleaning
The vandalism of renowned sixteenth-seventeenth century burial monuments at St. Mary’s parish church in the heart of Kilkenny city during the years either side of 2000 caused outrage and led one authority to brand their treatment as ‘a national disgrace’ (Curl 2013, 159). In 2014 the first phase of a project to conserve and restore these tombs, and others on the site, was undertaken as part of a wider repurposing of the medieval church building as a civic museum and exhibition space.
Graffiti removal was undertaken following extensive trials and research. A combination of non abrasive targeted steam cleaning and quick acting specialist Alkaline Gel Graffiti cleaning solutions (comprising dichloromethane, benzyl alcohol and ethanol solution) were used which allows the retention as much of the natural patina as possible. The approach was very slow and gentle with the expectation only to attempt to remove graffiti that was visually obtrusive to the monuments and where any graffiti material was offering huge resistance, it felt best to leave for fear of overtreatment. The key to retaining as much of the natural patina as possible.
The stone was firstly washed down and dampened and the cleaning product was painted directly onto the graffiti matter and left to act for approx 15-45mins. It was then scraped off and the stone washed down with copious amounts of water and a light solution of degreaser and neutraliser where necessary to ensure removal of all product. Where necessary the cleaning product was then reapplied and removed in the same manner two more times. There was a definite success in that the graffiti matter had substantially faded and the cleaning product had little impact on the natural patination of the stone surrounding the graffiti. Very stubborn strongly-pigmented graffiti material (likely spray paint) which had penetrated deeply into the limestone proved more difficult to remove and whilst it faded somewhat with treatment its complete removal may have caused damage to the stone surface and it remains visible.