Fabric: Red, slightly micaceous sandy fabric consistent with other Iberian types. Fine sandy fabric with some voids.

Glaze: Interior/Exterior green lead glaze with much surface decay [Note: no mention of glaze is mentioned on published mercury jars; this is the glaze description for the vessel from Jamestown Rediscovery].

Form: A small rounded jar with very thick vessel walls and an everted rim and splayed base.

Image from A Guide to the Classification of Medieval Ceramic Forms, (1998) Medieval Pottery Research Group, Occasional Paper 1, 10:19.

Discussion

Mercury jars, which are believed to be of Spanish origin from fabric analysis, have been recently identified in the vessel typology. Documentary evidence and residue analyses of these vessels found in contexts dating to the 15th century and later in Southampton and London have supported their function as mercury containers. They are distinctive in their small size and thick walls that "are consistent with the great value and density of the metal they held" (Brown 1995:321).

Mercury was used in early 17th-century Europe for silvering mirrors, medicinal purposes, as well as for the amalgamation and extraction of gold and silver from their ores. The need for mercury at Jamestown is most likely the result of the latter two functions. It is known from historical documentation that the first colonists were constantly searching for precious metals and thus would have required mercury for their tests. Jamestown Rediscovery excavations have revealed many refractory clay crucibles that were brought for the assays. In addition, John Woodall, a London surgeon who sent a fully equipped surgeon's chest to Jamestown in 1609, required that mercury be an integral part of the equipment carried by surgeons employed by the East India Company (Woodall 1617).

In the 17th century, mercury was primarily obtained from mines in Almaden, Spain, Eisenrz in Styria (Germany), and Idria (Yugoslavia) (Stenuit: 447). The use of Spanish vessels to contain the mercury may be indicative of the source of the mercury purchased by the English.

Mercury has been found on 17th-century Dutch shipwrecks stored in German stoneware Bartmann jugs and in glass case bottles capped with pewter. There are contemporaneous complaints of mercury leaks from stoneware jugs through invisible cracks that occurred during production of the vessels. The glass bottles also suffered frequent breakage. Attempting to cut their losses, merchants even tried shipping mercury in leather bottles within wooden kegs; but these often rotted from the humid environment in the ship's hold. Earthenware vessels were found to be the most satisfactory containers for mercury.



Sites
Jamestown Rediscovery, Midden 1 (mixed, ca. 1607-1635).


Prepared by Bly Straube