"Yukon Seasons" Restoration - Phase 3 - by Valery Monahan, Conservator
September 18, 2008 Filed in: Yukon Seasons Heist
I am well into stain removal and my opinion about the dirt keeps changing! I now think the black stain on the bear might be spruce resin.
There is more of that stuff in the holes in the antler just adjacent and a lot of it is quite transparent and yellowish to reddish. So, most of it has the appearance and consistency of resin and the really black bits of it might just be areas where it was exposed to loose dirt, coating its surface and making it look very dark.
I have been able to remove quite a bit from the bear and surrounding area with a fine needle.
Unfortunately, resins like this are quite difficult to dissolve without using oils of various kinds ... and those are difficult to control and can make stains, too. So, I have not been able to safely remove all of the original staining from this area, but I think it looks much better, overall. (See images below.)
Lots of other small dark stains have responded well to that most traditional of conservator cleaning agents: saliva. Some people have claimed that it is enzymes in saliva that make it work so well, but I've seen recent research that suggest its combination of polarity and relatively high surface tension are also important as they greatly improve its wetting power, pulling dirt and stain materials out of surfaces more efficiently. Rest assured that I use tiny, tiny, almost dry saliva swabs and then clear the saliva with tiny, tiny, almost dry water swabs. Spit has been used to clean many famous paintings and other art works, but this is not often discussed outside of conservation circles. "Mild enzymatic solvent" is the popular euphemism ...
I have two questions and they are both about the snot tape**. Do you use the tape kind, or the gun-dispensed kind? I am also curious about where (all) the snot tape was used. The snot tape residues on the mount and on edges of the antler are currently black ... not surprising since it is still really sticky and both the mount and the sculpture have been much handled and stored in dusty places. However, these very black snot tape residues have led me to wonder whether two similarly very black areas under the base of the skull are not mould, as I originally assumed, but actually more snot tape residues. If these areas were still sticky when the sculpture was stolen, it would make sense that they would now have thick layers of black grime covering them. The underside of the skull does not rest on the mount, however. So, my question is if you recall ever having snot-taped Yukon Seasons to something via the underside of the moose's skull ... maybe to facilitate carving?
**[Note: 'Snot tape' is an industry term for a very sticky, gummy, double-sided tape that can be balled up and used to stick things together temporarily. It is really, really sticky and has found many uses in the movie industry on sets, where things need to be stuck up temporarily on locations, etc. During the filming of a television series in Whitehorse, called 'Northern Town', Yukon Seasons was used in one of the sets (it did not make it to the final cut). The crew introduced me to snot tape as a way of adhering Yukon Seasons to its stand, so as not to be bumped off in the midst of filming. I continued to use it afterward, ensuring a reasonably permament, non-invasive bond, between sculpture and stand. It was probably due to the stickiness of the snot tape that the theives broke the sculpture when they removed it from the stand.]
The black grime under the skull is coming off, it is not visible anyway, but it would be nice to be able to say that it is not mould, if it isn't. The dark spots which brushed off the antler tines really were mould and, until I noticed the residues on the mount, I just assumed that what was under the skull was the same, but with much heavier growth. If it is actually something else, then the sculpture actually didn't have much mould growth at all. And that is a good thing ...
Here is a detail of the black staining under the skull. Note that it is more uneven looking than the staining on the tines was ... not quite the nice circular shapes you get with microbial growth. If you can remember putting snot tape there at some point, or if you are quite sure you didn't, please let me know.
The reason I am curious about which type of snot tape you use involves understanding its long term properties. Different adhesives respond differently as they age and if relatively heavy things are mounted semi-permanently with adhesives that tend to get brittle over time, it can be a problem. I'm getting an opinion on the long-term durability of the snot tape from my colleagues at the Canadian Conservation Institute and the type of commercial product you use will help them fine-tune their comments. I'll let you know what they say about its safety over the long-term.
Valery
(moose antler skull carving, moose antler skull sculpture)
There is more of that stuff in the holes in the antler just adjacent and a lot of it is quite transparent and yellowish to reddish. So, most of it has the appearance and consistency of resin and the really black bits of it might just be areas where it was exposed to loose dirt, coating its surface and making it look very dark.
I have been able to remove quite a bit from the bear and surrounding area with a fine needle.
Unfortunately, resins like this are quite difficult to dissolve without using oils of various kinds ... and those are difficult to control and can make stains, too. So, I have not been able to safely remove all of the original staining from this area, but I think it looks much better, overall. (See images below.)
Lots of other small dark stains have responded well to that most traditional of conservator cleaning agents: saliva. Some people have claimed that it is enzymes in saliva that make it work so well, but I've seen recent research that suggest its combination of polarity and relatively high surface tension are also important as they greatly improve its wetting power, pulling dirt and stain materials out of surfaces more efficiently. Rest assured that I use tiny, tiny, almost dry saliva swabs and then clear the saliva with tiny, tiny, almost dry water swabs. Spit has been used to clean many famous paintings and other art works, but this is not often discussed outside of conservation circles. "Mild enzymatic solvent" is the popular euphemism ...
I have two questions and they are both about the snot tape**. Do you use the tape kind, or the gun-dispensed kind? I am also curious about where (all) the snot tape was used. The snot tape residues on the mount and on edges of the antler are currently black ... not surprising since it is still really sticky and both the mount and the sculpture have been much handled and stored in dusty places. However, these very black snot tape residues have led me to wonder whether two similarly very black areas under the base of the skull are not mould, as I originally assumed, but actually more snot tape residues. If these areas were still sticky when the sculpture was stolen, it would make sense that they would now have thick layers of black grime covering them. The underside of the skull does not rest on the mount, however. So, my question is if you recall ever having snot-taped Yukon Seasons to something via the underside of the moose's skull ... maybe to facilitate carving?
**[Note: 'Snot tape' is an industry term for a very sticky, gummy, double-sided tape that can be balled up and used to stick things together temporarily. It is really, really sticky and has found many uses in the movie industry on sets, where things need to be stuck up temporarily on locations, etc. During the filming of a television series in Whitehorse, called 'Northern Town', Yukon Seasons was used in one of the sets (it did not make it to the final cut). The crew introduced me to snot tape as a way of adhering Yukon Seasons to its stand, so as not to be bumped off in the midst of filming. I continued to use it afterward, ensuring a reasonably permament, non-invasive bond, between sculpture and stand. It was probably due to the stickiness of the snot tape that the theives broke the sculpture when they removed it from the stand.]
The black grime under the skull is coming off, it is not visible anyway, but it would be nice to be able to say that it is not mould, if it isn't. The dark spots which brushed off the antler tines really were mould and, until I noticed the residues on the mount, I just assumed that what was under the skull was the same, but with much heavier growth. If it is actually something else, then the sculpture actually didn't have much mould growth at all. And that is a good thing ...
Here is a detail of the black staining under the skull. Note that it is more uneven looking than the staining on the tines was ... not quite the nice circular shapes you get with microbial growth. If you can remember putting snot tape there at some point, or if you are quite sure you didn't, please let me know.
The reason I am curious about which type of snot tape you use involves understanding its long term properties. Different adhesives respond differently as they age and if relatively heavy things are mounted semi-permanently with adhesives that tend to get brittle over time, it can be a problem. I'm getting an opinion on the long-term durability of the snot tape from my colleagues at the Canadian Conservation Institute and the type of commercial product you use will help them fine-tune their comments. I'll let you know what they say about its safety over the long-term.
Valery
(moose antler skull carving, moose antler skull sculpture)