Bronze Sculpture 101: Understanding Patina

As stated on wikipedia:

Patina (pronounced /ˈpætənə/ or /pəˈtiːnə/) is a film on the surface of bronze or similar metals (produced by oxidation over a long period); a sheen on wooden furniture produced by age, wear, and polishing; or any such acquired change of a surface through age and exposure. On metal, patina is a coating of various chemical compounds such as oxides or carbonates formed on the surface during exposure to the elements (weathering). Patina also refers to accumulated changes in surface texture and colour that result from normal use of an object such as a coin or a piece of furniture over time.

Patinas are restricted to exposed surfaces and are fragile (that is, they can flake off). One reason bronze is so highly valued in statuary is that its patina protects or passivates it against further corrosion. This natural patina is solid and seldom shows a tendency to flake. Brass is also resistant to corrosion, but it is, in the long run, not as attractive since local pitting shows against the shiny background.

The green patina that forms naturally on copper and bronze is often mis-named verdigris and usually consists of a mixture of chlorides, sulphides and carbonates. copper carbonate or copper chloride. Atacamite is another name for the patina compounds. Verdigris can be produced on copper by addition of vinegar (acetic acid) - such a verdigris is water-soluble and will not last on the outside of a building like a "true" patina.

One example of a patina is a green surface texture created by slow chemical alteration of copper, producing a basic carbonate. It can form on pure copper objects as well as alloys which contain copper, such as bronze or brass.

Artists and metalworkers often deliberately add patinas as a part of the original design and decoration of art and furniture, or to simulate antiquity in newly-made objects.

A wide range of chemicals, both household and commercial, can give a variety of patinas. They are often used by artists as surface embellishments either for color, texture, or both. Patination composition varies with the reacted elements and these will determine the color of the patina. For copper alloys, such as bronze, exposure to chlorides leads to green, while sulfur compounds (such as "liver of sulfur") tend to brown.


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Bronze Sculpture 101: Fixing minor blemishes

In this post we'll be talking about repairing and/or maintaining your bronze sculpture in the event that something happens to it. Bronze is a very durable, long lasting metal that ages well. However, it's not indestructible. On occasion, some wearing or scratching of the patina may occur; during movement of the piece from one location to another. And, rarely, cracking can occur when when the weld holding two parts of the sculpture together comes loose. The beautiful part about bronze is that these are both very easily corrected. For scratches and scrapes that may remove the patina down to the bare metal, just a simple re-patination is all that's required. For minor cracks, the area around the crack has to be sanded to the bare metal then brazed and welded. Once the weld is done and smoothed, a simple re-patination is done and the piece will look as good as new. Preventative maintainance goes a long way in preventing these type of issues from occurring. Being careful when moving the piece and putting a protective coating on will help your sculpture stand up to the elements and last for many many years to come.

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Snow, Snow, and more snow! Will it ruin a bronze sculpture or statue?

With all the bad weather, and record snowfalls for much of the country, you may be wondering how it will affect your bronze sculpture, statue, or fountain. The good news is there's not a lot to worry about. Bronze is designed to withstand the elements, which is what makes it such an appealing medium in the first place. No matter the conditions, rain, sleet, or snow, it will continue to keep its beauty. In fact, a little snow can add to the elegant look and make people really take notice.

Buying Bronze Sculpture 101: Patina or paint?

When you read some of our descriptions you'll often notice that we mention that a piece is colored with an all natural "patina" finish. You may ask yourself, "What the heck is a patina?" Bronze is made up of a few metals, mainly copper, and some other alloys. These metals, when heated, react in a certain way to different chemicals and acids which produce a certain color. The real look of a bronze sculpture that has no patina is that of a new penny. The "traditional" look of bronze statues, that dark brown coloring like our wild horse, is actually a patina that was applied to the heated metal to create the color. Bronze can be colored in several shades using this chemical reaction process. Most often they are greens and browns. If you want your bronze statue or fountain to have a more realistic look,like our Mermaid with 8 dolphins, traditional paint must be used. An oil based paint, like automotive grade, gives a shinier, almost porcelain appearance, whereas acryllics will be more of a matte finish. In both cases a protective coating is applied to maintain the look for a long time.
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Buying Bronze Sculpture 101: Preserving Your Bronze

After you purchase your new bronze sculpture, statue, or fountain you'll want to ensure that it keeps its beautiful look for many years to come. Now, you may want to leave the piece alone and have it naturally "age" over time. A lot of people like the pieces even more once they begin to get that Statue of Liberty look to them. If you're one of these people, just sit back and enjoy your piece as is and it will weather over time. However, if you'd like the piece to retain its original look, like our Eagle, some protection will be required. When these piece are created they're polished with a wax like Kiwi Boot polish which gives them that beautiful luster. Eventually, that initial coating will wear off and the weathering process will begin. To prevent this you can put on a new coating of the same type of polish, plain paste wax, or a clear spray on laquer. We recommend Permalac. It comes in a spray can and is easy to apply. You definitely never NEVER want to use any automotive grade waxes or abrasives as it will remove the finish rather than protect it. A little simple maintenance every few years will keep your bronze looking as good as the day you bought it!

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Bronze Sculpture Statue Patina Application Process

This video was taken on our last trip to the foundry. It shows part of the patina process for the bronze statues and sculptures we have. It's a very cool process as you can actually see the metal change before your eyes. People don't always realize the amount of work that goes into creating these pieces but they are all individually hand colored. Just another reason our pricing is so fantastic. You just won't find better prices for truly hand made sculptures or statues.