QUANTIFYING TRENDS IN STONE USED FOR BUILDINGS, STATUARY, AND OTHER USES OVER TIME WITH ARCHAEOLOGICAL SERIATION CURVES

Many publications have discussed trends in stone use over time, but such discussions have been, for the most part, qualitative. Such trends can be shown in a quantitative manner using seriation curves, a methodology commonly used by archaeologists and anthropologists, but underused by geologists. The technique was originally developed for use in plotting changes in cultural items such as pottery types over time, graphically representing time series. Such graphs have also been used by a number of authors to show changes in stone used for gravestones over time.

Building on use for gravestone analysis, seriation curves can also be used to illustrate changes in stone and other material used for sculptures, buildings, and other aspects of geological material culture. Seriation curves can be used to plot already existing data gleaned (data-mined) from publications and websites as well as from newly collected data. What is needed in either case is a stone type and a date of completion, construction, or dedication. Larger data sets are better, but even smaller data sets can result in illustrative seriation curves.

Seriation curves were constructed for building stone used for the exterior of houses of worship in northeastern Ohio (based on Hannibal, 1999) and for stone types (marble, granite, sandstone) and bronze (and other metal) used for Civil War statuary monuments (based on a Cincinnati History Library and Archives website on Civil War Monuments in Ohio). Curves for churches show early dominance of sandstone with subsequent but episodic dominance of limestone and dolomite. Curves plotting Civil War statuary monuments indicate an early post-war preference for marble versus granite, but a subsequent preference for granite in the post-war decades. Bronze and other metal statuary, however, came to dominate stone in the 1920s. The seriation curves for these and other cultural items made of stone offer interesting similarities and differences that are related to availability, transport, weathering characteristics and other stone properties, and cultural preferences.