Subject: Shagreen
Emily Lin <nilylime [at] hotmail__com> writes >I am a student of the art conservation program at Queen's >University. I am writing to request sources of shagreen for the >microscope box that I am treating. The box has a shagreen covering, >which was dyed green, and much of it has been lost. > >In a previous posting on this list, I learned that shagreen consists >of the untanned skin of sharks, with the placoid scales being >smoothened and polished. I did an extensive study of shagreen for my thesis a couple of years ago and came upon many misconceptions in the process, mainly that most people automatically assume that the shagreen they have is shark skin when in fact rayskin is much more common. Even the V&A managed to mis-label one of their exhibits, so cursory identification of the various materials can be problematic. You don't say whether your box covering is sanded flat or is nodular, or what shape the placoid scales are. It is generally easy to tell the basic difference between ray and sharkskin: ray has more rounded scales of varying sizes and shark scales are more regular, small (generally around 1mm or so across) and diamond shaped. If the surface is unsanded and the nodules are rounded, the previous respondent is correct in saying that it can be difficult to tell if the covering is actually fish leather at all. However, the nodules of animal leather shagreen usually tend to be fairly uniform and repetitive in size and shape, whereas those on unsanded rayskin are very obviously irregular in size and 'mesh' together rather better. Also, careful microscopic inspection can reveal grain lines, pores and hair follicles in the surface if the material is animal leather. Failing this, inspection of the rough edge left where material is missing can reveal rounded indents where ray scales have detached. In addition, the nodules of embossed animal shagreen can often be made to depress slightly where ray shagreen scales are completely solid. The reason you are unlikely to find sharkskin which has either not had the denticles sanded flat or had the scales completely removed lies in the abrasive quality of the natural skin--indeed, it was originally used as sandpaper and to cover the boot-soles of shark fishermen to prevent them slipping on wet and greasy ships decks, so that gives you an idea. It certainly isn't a material to be used decoratively in its natural state as a rule, unless it is something like smoothhound (mustelis canis), which can be used unsanded but which still has a slightly abrasive quality. Once you have determined the type of shagreen you have, there are some suppliers of it, both sanded and unsanded in the case of rayskin, although they are few and far between. I did find one who was kind enough to send me a sample card without charge and I can let you have his details if you would like. I actually found him on eBay of all places, supplying rayskins for decorative coverings. It is as well to be aware, in your hunt for replacement shagreen, that fish skins obtained from some of the more remote tanneries of the world have very likely have been treated with arsenic to prevent rot and would need very careful handling. If you would like to send me a picture of the covering you have, I would be happy to try and help to identify it. Ann Walker Unicorn Conservation and Restoration Studios Lincoln, UK +44 7890 373502 *** Conservation DistList Instance 21:56 Distributed: Friday, April 18, 2008 Message Id: cdl-21-56-005 ***Received on Thursday, 17 April, 2008