Low-fired ceramics with coarse temper tend to be delicate and crumbly. This lamp has broken into three large pieces with another smaller piece near the center about to detach. There are crumbs of material in the box. The break edges are the same dark color as the surface. Does this mean the pottery is made from dark clay to begin with, or that it was broken in a fire and the exposed surfaces all became dark? If you don’t know the mechanism of damage, just describe the evidence of what you see.
Photo credit: Alaska State Museum collection II-A-7014
This lamp is overall gray in color, with a paler region on most of the interior and darker areas along the sides that appear to be scorched. If you are unsure of the reasons for the features you see, just be descriptive.
Photo credit: Alaska State Museum collection II-A-5672
This lamp has a very dark surface and there are areas of thick accretion that might be moss or plant matter. These accretions are firmly attached.
Photo credit: Alaska State Museum collection II-A-2564
This small pitcher from a shipwreck has localized cracks, including through the handle. There is damage and loss in the spout area. The break edges at the loss include some areas of yellow. This could mean that the pitcher was broken long ago and the break edge became stained but then was broken further, resulting in break edges that are white.
Photo credit: Alaska State Museum collection 2015-6-68
Ceramics are porous, and exposure to dissolved salts can get into the structure of the ceramic from groundwater, seawater, or use. Those soluble salts can crystallize out on the surface of the ceramic. This example is unglazed, meaning it does not have a thin glassy later fired onto the surface. If a ceramic is glazed and salty water penetrates into the pores through gaps in the glaze, the salt crystals can become trapped behind the non-porous glaze when it dries. In that case, the force of the crystal can cause a small chip to spall off the surface.
Photo credit: Alaska State Museum conservation research collection
This is an example of salts crystallizing on the surface of a crock used to make kimchee.
Photo credit: Ellen Carrlee
The underside of a ceramic might have a hallmark like this. Mention the presence of a hallmark, but describing in detail is best left to another section of the object record. All the tiny cracks are in the glaze, or glassy outer layer of the ceramic. This fine network of cracks is called crazing or crackle, and is caused by the glaze being under tension. You can see that some of the cracks are darkened with stain, and others are not. Usually, a crazed ceramic is still stable.
Photo credit: Alaska State Museum collection 2008-11-70
These potsherds from a shipwreck show varying degrees of staining, crazing, chipped edges, and wear.
Photo credit: Alaska State Museum collection 2008-11 accession
There is obviously an issue with the surface of this pottery dish. Overall, the surface appears delicate and is rough and slightly flaky. The interior surface appears lighter, less glossy (more matte) and perhaps more flaky. The incised decoration is somewhat obscured. Does this mean the interior is more damaged, or that we are seeing residues of whatever the dish held? If you don’t know, make sure your condition description captures both possibilities.
Photo credit: Alaska State Museum collection II-A-120
This small dish recovered from the ocean floor has minor abrasion to the rim and some orange staining, especially around the edges. There are no obvious cracks and the glaze is not cracked, either. There is a mark on this one for the Canadian Pacific Navigation Company. Marks and decoration on ceramics can be either under the glaze, which is usually stable, or painted on top of it, which is rather vulnerable and can suffer from abrasion.
Photo credit: Alaska State Museum collection III-O-891
This “thunder mug” from a shipwreck has been reconstructed from broken pieces. Once clue is the difference in color of some of the fragments. Another clue is the triangular void where a piece is missing. If a ceramic has been reconstructed in the past, it might be unstable and vulnerable to coming apart again, depending on the kinds of adhesives and techniques used to do the repair. If possible, try to find and include the repair information in the object record. The most important points would be what materials were used to do the repair and the date it was done. If you are lucky, there might even be photographs or a treatment report somewhere.
Photo credit: Alaska State Museum collection 2015-6-145
