Rose-Cut Gems from the Baroque Era
Colored stones from the Baroque era fashioned as rose cuts have received little attention to date. Even the colored stone rose cuts incorporated in notable collections, such as the Cheapside Hoard discovered in London in 1912, have not been studied in detail, and only very limited further examples are depicted and described in gemological texts. Recent work with five objects of liturgical insignia and electoral regalia belonging originally to the archbishops and prince-electors of Trier and Cologne has thus offered an opportunity to augment available information. All of these pieces date to the second half of the seventeenth century. Although the table cuts from that era were still quite simple, consisting of an upper flat table facet surrounded by one or two rows of step-cut facets, the rose cuts were enormously varied and complex while still generally following a symmetrical pattern in the facet arrangement. The goal of the study was to contribute to filling a gap in the historical information on gem cuts by offering an overview of the many rose cuts used for colored stones in the second half of the seventeenth century.
Rose cuts encompass a variety of faceting arrangements, all of which lack a flat table. In contrast to the considerable literature on the use of rose cuts in diamonds, there has been a dearth of information regarding their use in colored stones.
Although today the interested gemologist, art historian, or jeweler might be able to find various photographs or drawings of art objects exhibiting rose-cut colored stones, no systematic evaluation of such cuts is available in the literature. While nineteenth-century texts may present a broad selection of table cuts, along with covering the three traditional rose cuts for diamonds, other gem cuts without flat tables are not shown or described as being commonly available. Presumably such objects were not known to the authors of these treatises and were thus considered extremely rare, an estimation borne out by their treatment in Schrauf (1869). There, a rose-cut garnet with a flat base and eight rhombus-shaped facets forming a central dome was drawn and characterized as a unique gem fashioned in the eighteenth century or before, and a similar stone with eight kite-shaped facets topping the central dome was also described as unique and very rare.
Rose cuts are still produced from multiple gem materials, primarily garnet (figure 5, left and center) and quartz (figure 5, right), and thousands of facet designs including numerous rose cuts can be found by interested users and cutters in modern texts (e.g., Long and Steele, 1979–1989) and online databases (e.g., FacetDiagrams.org). However, these are mainly cuts developed in the nineteenth or twentieth century, and the publications are silent as to whether the designs find any analogue in objects of eras past.
The colored stone rose cuts featured in the current study came to light during examination of five objects of liturgical insignia and electoral regalia. Four were from what is known as the Trierer Kurschatz (the treasury of the archbishops and prince-electors of Trier, who were one of the seven electors of the Holy Roman Empire1). The work began principally with gemstone identification at the time the collection was publicly presented in October 2017 (“The Munich Show,” 2017). The investigation continued at the Diözesanmuseum Limburg (Museum of the Roman Catholic Diocese of Limburg), where the treasury is normally exhibited, with the focus turning in part to the cuts of the stones. It soon became apparent that these artifacts, dated to the second half of the seventeenth century, contained numerous colored stones with rose cuts differing markedly from the standard cuts presented for diamonds in gemological texts