Unfired decoration on Campanian ceramic

In response to Naoko Fukumaru's question concerning unfired
decoration on a Campanian ceramic, I would suggest the following
reference:

    Noble, Joseph V.
    The Techniques of Painted Attic Pottery
    New York: Watson-Guptill, 1965.

>Major iron, minor calcium and lead, and trace of zirconium, titanium
>and manganese were detected on the black paint by XRF analysis.
>Major lead and trace of calcium and iron were detected on the white
>paint. Major lead and iron, minor calcium and faint trace of mercury
>were detected on the pink paint. Major iron, minor calcium and trace
>of lead and zirconium were detected on the ceramic body.

>From the description and solubility of the black paint, I would
guess that it is exactly that, a "black paint", and it is not
original to the piece.  The original black glaze (or "gloss" as it
is now sometimes referred to) that was applied on Greek vases is a
sintered engobe, and would not be soluble in solvents.  Rarely,
particularly on Hellenistic pottery (and specifically on
white-ground lekythoi), the white, pink and orange slips are applied
post-firing, but in many other applications, these slips are
clay-based and fired on.  Without seeing the vessel, I would think
you have a heavily restored object (particularly given the metallic
oxides you are detecting in analysis).

Stephen Koob
Conservator
The Corning Museum of Glass
One Museum Way
Corning, NY 14830
607-974-8228
Fax: 607-974-8470


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                  Conservation DistList Instance 18:43
                  Distributed: Monday, March 14, 2005
                       Message Id: cdl-18-43-005
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