Rehydration/Rehydroxylation Kinetics of Reheated XIX-Century Davenport (Utah) Ceramic

Rehydroxylation (RHX) dating has recently been proposed as a new chronometric dating tool for use on archeological fired-clay ceramics. The technique relies upon the well-known characteristic of reheated porous ceramic vessels to regain water through a two-stage process (rehydration and RHX), where the kinetics of second stage has been shown to follow a (time)^1/4 power law at temperatures of 13°–50°C. In this study, experiments were conducted in which the mass measurements taken from 19th-century ceramic artifacts could be described by the (time)^1/n power law over a wide range of temperatures. This finding has led to the formulation of a new empirical equation, which describes the observed ceramic's rehydration and RHX behavior without the need for identification of RHX stage. As part of this study, the mineralogy of the ceramics and their thermal properties have been evaluated. The instantaneous effect of humidity on mass measurements was demonstrated to be the principal source of error. RHX dating shows promise, and after more research, the technique could become an important archeometric tool.