Tuesday, January 26, 2016

King Tut is now minding his own beeswax

Exactly a year ago, I blogged about King Tut's iconic mask being damaged, specifically that the beard had fallen off and was hastily repaired by the 3 Stooges and some 5-minute epoxy (all of which exposed him to TOXIC! levels of BPA). A German art conservator was brought in last fall to attempt a repair.

The National Geographic website reported back in December on his efforts. These included removing the epoxy by heating it and using wooden scrapers to avoid further damage to the mask. Prior to this, they performed a number of scans on the mask and discovered that a previous repair from 1946 had been done using a soft solder. But in this repair, they used an adhesive with ancient roots - beeswax.

As you might guess, beeswax adhesive is not straight beeswax since it is just a softish waxy material with little or no adhesive properties. It is typically mixed with rosin to increase the tackiness. That this is a "natural" adhesive is a selling point, but the repair is certain to not last an eternity (too bad, as Tut will need it that long). Another repair will be needed at some point down the road, but removing the beeswax adhesive should be relatively simple compared to an epoxy.

I wonder how they decided on beeswax, and more importantly, how much (and which) rosin to add to it. Like any tackifier, too much rosin will decrease tackiness, so getting the levels just right is important. Rosins also have varying degrees of unsaturation, all of which will be oxidized over time and potentially changing the adhesive. It would be nice to think that this was all studied and analyzed in great detail, but I suspect that might not be the case.

As for the fate of the artifact-altering-associates, they are facing trial for their "work". There is no word on what potential sentences they are facing, but I think gluing their fingertips together with an epoxy or a cyanoacrylate would be a good start.

Previous Years

January 25, 2015 - King Tut and BPA

January 26, 2012 - Viewing History through an Oil Refinery

January 26, 2011 - My Most Embarrassing Moment at Work

January 26, 2010 - Phosgene Death

January 26, 2009 - More on Dow and Rohm & Haas

January 26, 2009 - Biodegradation of Polymers

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