Abstract

In the eighteenth century, the emergence of a neo-classical style in architecture created a growing demand for a range of classically-inspired products - not only for architectural decoration but also for ornamentation of the garden. Producing individual items in stone, however, was time-consuming and expensive, so cheaper clay-based alternatives were adopted, most notably from manufacturers such as Coade (1769-1830), Blashfield (1840s-1875) and Doulton (1854-1890s).
The artefacts of these manufacturers are now considered of high historic value and significance and their identification is important, not only for the historical record, but also for provision of the evidence necessary to carry out informed conservation. As the sale and copy of moulds was common practice during the eighteenth and nineteenth centuries, stylistic considerations do not provide reliable identification.
Through the analysis of 24 historic objects of garden statuary and ornamentation, this research evaluates the use of portable X-ray fluorescence spectroscopy (pXRF), and more specifically element profiles, in identifying, and differentiating between the products of Coade, Blashfield and Doulton. Key questions around heterogeneity and representative material analysis are addressed.
Despite the inherent heterogeneity of these materials, it is shown that discrimination is nevertheless possible using pXRF, primarily due to the significant differences observed across a range of elements at both macro- and trace-level. Objects of known provenance from Coade, Blashfield and Doulton produced three distinct and statistically significant groups demonstrating that the data reflect the composition of the bulk material – rather than surface characteristics.
Through identifying the main discriminators for the Coade, Blashfield and Doulton materials, a simple presumptive test is proposed that can be used in an initial evaluation of any unsigned works. Analysis of a selection of unsigned objects with a probable Coade, Blashfield or Doulton provenance was in many cases successful in confirming the documentary evidence. A few objects, however, presented anomalous element profiles. These most likely result from past conservation treatments or polychromy - the two major limitations of the technique.