I left my wife and grandchildren in the record cold of 29 degrees below zero in my hometown of Montpelier, Vermont and headed off to a balmy 50 degrees in Athens, Greece – my latest assignment for the Cultural Heritage Office (CH) of our State Department.
CH is a small talented team of art conservators who take care of all the art, antiques and historical structures in our overseas embassies and ambassadors’ residences.
CH has been one of my clients for a number of years. This past year they asked me to join them full-time, and it’s been a wonderful ride with a new travel adventure nearly every month. This trip I tackled this 10′ bronze of George Marshall standing in front of our embassy in Athens.
Bronze is a marvelous metal. A very durable mix of copper and tin (brass is copper and zinc) first appearing over 5000 years ago in the Western Asian civilization of Sumeria. It’s believed that bronze was discovered when copper and tin-rich rocks were used for campfire rings. Bronze tools, weapons, armor, and building materials soon proliferated because they were harder and more durable than their stone and copper predecessors. Bronze so transformed the world that we call its first 1700 years the ‘Bronze Age.’
Add ‘patina’ and a bronze sculpture is virtually indestructible. Here’s where I get to show off about the word ‘patina.’ You see, patina is often misused even by experts! Here’s a real know-it-all, Dr. Lori Verderame, to set us straight,
“Patina is a process which relates to the application of color or pigment onto a work of cast metal sculpture. The patination process occurs at a cast metal foundry whereby pigment is applied to a metal sculpture to enhance the look of the metal….Patination is applied to a surface, it is NOT a result of the aging process which occurs over time….”
There you go! You’re now smarter than Wikipedia and anyone else who thinks patina is oxidation such as when copper turns green. The green on copper is strictly speaking not patina.
The interesting thing about patina is that it was invented to stop bronze sculpture from oxidation, or as us common people like to say, rust! Like paint, patina does a great job protecting metal sculpture, but it doesn’t completely stop rust. The other interesting thing about patina is that it’s a nasty chemical that’s highly toxic until it dries!
- Related Projects:
- Art Conservation of the World’s Tallest Buddha
- Sculpture Repair at the Winfield House
- Sculpture Installation at the US Embassy in Athens
- Art Repair at the Denver International Airport
So sculpture nerds like to put something over patina for added protection. Here’s where I come in. Standard maintenance for bronze sculpture is a coat of natural and durable wax such as carnauba every 6 months. I personally believe this is a waste of time, because it doesn’t last a month on outdoor sculpture and isn’t needed on indoor sculpture.
Thanks to the folks over at Everbrite, we now have a better way to protect outdoor metal sculpture. It’s a thin polymer that protects metal surfaces from oxidation and lasts 5 years. In the world of uppity art conservation, you just can’t throw out the traditional wax treatment unless the alternative is tested over time and reversible, meaning you can take it off. Everbrite has been around for 30 years and is entirely reversible. Oh, and a shout-out to Jenn who can ship it anywhere!
Using Everbrite’s satin finish, I’m slowly but surely coating all the outdoor metal sculptures at our embassies and ambassadors’ residences. Easy to apply after a quick cleaning with a solvent, Everbrite dries for a second coat in just 2 hours, completely drying in 2 days.
The only problem with this product is a minor one. Sometimes a dark bronze sculpture has a gorgeous green oxidation that you’d like to preserve. Everbrite will turn this bright green into dark green as if it’s wet. A good example of this is the sculpture below which is outside the US ambassador’s residence in Oslo, Norway. It is entitled ‘Spirit of the Dance’ by Kaare Kristian Nygaard (1903-1989). Notice the beautiful bright green copper oxidation against the dark patina. This is also a good example of how patina is not the best protection against oxidation. One might not coat this sculpture in order to preserve the bright green color. On the other hand, this sculpture is rusting! I have to weigh beauty against deterioration, so I’m likely to coat this one, too!
Here’s another example. This is a large bronze vessel in the center of a fountain in the back yard of our ambassador’s residence in Tokyo. The stunning green and orange oxidation is so beautiful I’m not going to touch it! And the bronze walls of this object are so thick that even though it is ‘rusting’ it will last several hundred years.
Here is another bronze sculpture I coated at the Athens Embassy: