Thursday, June 21, 2012

Artifact Conservation

     While I do the minor cleaning and repairs needed for the artifacts in the museum’s collection, there are jobs which are beyond my abilities.  A professional conservator is required in these cases.

    I would first like to clarify that there is a difference between conservation and restoration.  The goal of restoration is usually to bring an object back to its original appearance.  The goal of conservation is bring the artifact back to a stable condition.  Though improving the appearance of the artifact can be one of the objectives, it is not the main one.  In some cases, conservation of an artifact can result in leaving evidence of wear, or other “imperfections”.  Preserving the artifact and its history is the main goal here, not appearance.  Additionally, unlike restoration, any conservation work done is reversible.
     We are very fortunate at the NMCWM to have a volunteer who is a retired conservator and who can occasionally donate his time and talents in working on some of our artifacts.  He was recently able to stablize a surgeon's leather field case for us.  It was affected with red rot, and was displaying the characteristic powdery-red surface and weakened areas.      

This is the field case before treatment. You can see a reddish tinge to it. Not visible in the photo are small salt crystals on the surface of the leather. The straps were very thin and brittle. Even when I handled it very carefully, my white gloves would turn red where they contacted the leather.

Here is Spencer working on the case. He carefully removed the crystals from the leather and treated it with a consolidant called Cellugel which is absorbed into the leather and dries very quickly. He then applied a colored shoewax to the exterior surface.

The case not only looks much better, but it is now stronger and less brittle. Though the red rot did do some damage, the case has now been stabilized. 

     Another artifact which had professional conservation work done on it is the commission pictured below.  The document was in fair condition when it was acquired.  It was somewhat yellowed and faded and had some surface dirt, and it had been stored folded for many years.  The document was weak along all the fold lines, and one segment was completely detached.

This is a commission for Lt. John Henry Dye, 25th PA Infantry. He drafted maps for the Battle of Gettysburg. We have this document because his wife, Clarissa Jones Dye, was a Civil War nurse. You can see that the document is yellowed and in two pieces.

This detail photo shows damage along fold lines. This is a good reason to store paper items flat and unfolded!

     The commission was sent to Cleveland Conservation of Art on Paper.  The conservator reported the treatment as follows:  The surface of the paper was cleaned in the non-image areas, using grated polyvinyl eraser crumbs.  The paper was immersed in deionized water conditioned to a pH of 8.0.  As a result, the paper became lighter in color and the acidic content was lowered.  The back of the paper was sprayed with a very light alkaline reserve spray of magnesium oxide.  This will help to keep the acidic content of the paper lower.  The tears were mended and the weak folds were reinforced with kizukishi conservation paper and zin shofu wheat starch adhesive.  And finally, the document was placed in a stable, archival quality paper folder, which will allow the gradual migration of acids out of the document and into the folder paper while it is in storage.

As you can see in this photo, the document is now in much better condition than when we received it, and is much better preserved for the future.

     It is amazing what can be done for these artifacts!  It is fascinating to me, and I have to admit that if I had to pick another career, I’d definitely look into the conservation field.

Photos courtesy of the National Museum of Civil War Medicine

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