The following information is intended to answer some of the most frequently asked questions we receive. If you don't find the answer to your question here, please feel free to contact us for more information.

• What is bronze?
• What is "cold-cast" or "bonded" bronze?
• How do I know if my sculpture is bronze?
• Why is my sculpture changing color and what should I do about it?

• How should I care for my bronze sculpture?

• Should I repair/restore my sculpture?

• My sculpture has been damaged and I want to have it restored. What kind of results can I expect and how do I proceed?

 

What is bronze?
Bronze is a metal alloy comprised mostly of copper (about 95%). The other elements in bronze can include phosphorus, manganese, aluminum, and silicon. Sculptures cast in bronze are created using the lost wax casting process and are sometimes referred to as hot-cast bronze.

What is "cold-cast" or "bonded" bronze?
Cold-cast bronze, also known as bonded bronze, is a mixture of resin and bronze powder. Sculptures made of cold-cast bronze are created by pouring the resin/bronze mixture directly into a mold. This method of creating sculptures bypasses the lengthy lost wax casting process and is, therefore, an inexpensive alternative to hot-cast bronze. In general, cold-cast bronze is not have the strength and longevity of hot-cast bronze.

How do I know if my sculpture is bronze?
You can use any of the following methods to determine whether your sculpture is hot-cast bronze or cold-cast bronze:

  1. Feel the weight of the sculpture. A hot-cast (metal) bronze sculpture will be quite heavy, while a cold-cast (resin) sculpture will feel fairly light weight. For example, a small hot-cast bronze sculpture (about 12" tall) might weigh 6-10 pounds, while the same sculpture cold-cast will weigh only a couple of pounds.

  2. Lightly tap a hollow part of the sculpture with the wooden part of a pencil. If your sculpture is metal, the tap will ring. If your sculpture is made of cold-cast bronze, it will produce a dull "thud."

  3. Finally, on an inconspicuous area of your sculpture, for example, on the bottom of the piece, scratch a small area to reveal the material under the patina. If the revealed area appears bright gold in color, your sculpture is metal rather than cold cast resin.

Determining whether your sculpture is bronze, brass or some other similar alloy can be more difficult. In general, brass has a slightly lower copper content, so may appear more yellow in color, while bronze may appear more golden in color. Sculptures made of spelter, or pot metal, will be fairly light weight and appears grey in color.

Why is my sculpture changing color and what should I do about it?
Any metal sculpture, whether it is bronze or another metal, will likely change in appearance over time. A number of factors can affect the way a metal sculpture ages. These include:

  • Environmental factors (for example, humidity, exposure to salt air, extreme sunlight, handling, and contact with water and/or chemicals). A good maintenance program is the best way to guard against further undesired changes to patina and possible metal corrosion.
  • The original patina and finish. Some of the chemicals used during the patination process hold up better over time and in certain conditions than others. For example, the chemical that produces a white patina is fairly unstable and is not suitable for sculptures that will be installed outside, and a red patina will often darken or fade over time. Regardless of the type of patina used, any sculpture must be well sealed after patination (with either wax or lacquer). This finish must be maintained to preserve the underlying patina.
  • Proper maintenance. If a bronze is properly maintained over time, it should age nicely and restoration should not be required. However, if a sculpture is left unattended for a period of time, it might collect layers of dust, dirt, or chemical/mineral build up that should be removed to preserve the patina and prevent possible corrosion.

Some people enjoy watching the finishes of their sculptures "evolve," while others prefer that their sculptures retain the original (like-new) appearance. If you are unhappy with the appearance of a sculpture that has begun to change color, we can clean and seal the piece, or we can remove the old patina and apply a new patina and finish. The questions at the bottom of this page should help you decide what to do in your particular case.

How should I care for and maintain my bronze sculpture?
At a minimum, you can keep your sculpture clean and dust free using a soft cloth, feather duster, or soft-bristle brush. NEVER use a chemical cleaner or metal polish on your sculpture. Doing so will damage the finish, often severely. If you must, you can use a very small amount of mild soapy water to clean areas that do not come clean from dusting.

Every 6-12 months for indoor sculptures and every 4-6 months for outdoor sculptures, after cleaning your sculpture, place it in the sun for a few hours (or carefully heat it with a hairdryer) and apply a thin layer of Tre-wax using a soft natural-bristle brush. After the wax has dried to a haze, buff your sculpture with a soft clean cloth.

Should I repair/restore my sculpture?
When deciding to restore a damaged sculpture, consider the following questions:

  • How noticeable is the damage?
    If the damage is minor, it might be possible for you to continue to enjoy the sculpture by simply positioning it in a manner that the damaged area cannot be seen.
  • Will changing the finish on a family heirloom or an antique impact its sentimental or monetary value?
    We strive to repair damaged sculptures such that the restoration is unnoticeable and that the rest of the sculpture is effected as little as possible, however, there are cases where the sculpture cannot be restored to its pre-damaged condition. For example, if spot matching a patina is not possible, an entire sculpture might require a new patina to disguise the repair. The new patina will match the original patina as closely as possible, but will not be identical. In these types of situations, you must consider the sentimental and monetary impact of restoration. On the other hand, you must also consider how leaving the damage unrestored impacts the sculpture's value.
  • Is restoring my sculpture worthwhile?
    If a sculpture that you like and intend to keep is damaged to a point that you no longer enjoy displaying it, restoration is well worth the cost. If, however, you intend to restore a damaged sculpture for resale, you should consider whether the money you will have invested in the sculpture and its repair can be recovered.

My sculpture has been damaged and I want to have it restored? What type of results can I expect and how should I proceed?
The results we can achieve during restoration depend on a number of factors including the extent of damage, the type of material used, the age of the piece, etc. For examples of the types of repairs we can do, view completed sculpture repairs.

For an estimate for repair/restoration, please email justin@bronzeartwork.com and briefly describe the damage. Please include measurements and the estimated weight and age of the piece. If possible, it is extremely helpful for you to include photos of the sculpture with close ups of the damaged area.