How To Restore Patina On A Copper Sink

How To Restore Patina On A Copper Sink

Over time, copper fixtures form a beautiful, deep patina as it reacts with oxygen. The patina, which is the result of the creation of copper oxide, offers a stunning, eye-catching hue. Some folks love the darker color, while others prefer the sleek, shiny looks of brand-new copper. 

While restoring a copper sink to its original shiny state isn’t difficult by any means, restoring the patina can be tricky. Why? Patina occurs naturally, making it complicated to replicate the exact degree of color with a forced reaction. 

However, if you have a few random stark, shiny spots in your copper sink and want to restore the rich, deep color, we have a few options for you.

How Do I Keep My Copper Sink Dark?

Sinkology K614-D66 Lange Farmhouse/Apron-Front 32 in. Single Bowl Grid, Disposal Drain, and Care Kitchen Sink Kit, 32 inch, Antique Copper

The key way to keep your copper sink dark is maintenance. If you leave certain objects in the sink or use specific cleaners, you’ll ruin the patina. This can leave streaks of shiny copper peeking through the patina. While this is great if you’re trying to bring the shiny surface back, it’s not ideal when you want to preserve the patina. 

So, to keep your copper sink dark, make sure you follow these tips:

  • Don’t leave any acidic foods in the sink, including tomato sauce, etc.
  • Dry the sink out at the end of the day.
  • Don’t leave cans in the sink.
  • Avoid using harsh scrubbers (like steel wool) to clean the sink.
  • Avoid using acidic cleaners on the surface.
  • Use mild cleaners, such as dish soap and warm water, to clean the surface. 

If you’re careful, you can keep the patina covering the copper consistent and beautiful. However, when accidents happen – don’t worry. As time passes, the patina will naturally restore itself. If you don’t want to wait for the sink to do its thing, you can try to accelerate the process. 

It’s vital to note that some of these methods may ruin your sink, as they’re designed for specific types of copper sinks. For example, if you use a method for restoring the patina on an unsealed copper surface, you may remove the patina entirely.

So, before you proceed with the following methods, make sure you know what kind of sink you have and are aware of the potential results. 

How To Restore The Patina On A Copper Sink

Sinkology K2010-BD66 Adams Farmhouse/Apron-Front 33 in. Double Bowl Grid, Drains, and Care Kitchen Sink Kit, 33 inch, Antique Copper

There are a couple of different methods you can use to restore the patina on your copper sink. Some methods work best for unsealed copper, while others are better for sealed copper sinks. If you’re not sure which option is best for you, we recommend seeking the assistance of a professional. 

This way, you can pass the process to a knowledgeable individual who knows the ins and outs of copper and its patina. If you’re up to trying to restore the patina yourself, here are a few different methods. 

Wait It Out

Consider waiting it out before you jump the gun and try various chemicals and methods to restore the patina. The patina will naturally restore itself over time, so this is usually the best option if you’re willing to wait.

Avoid measuring the patina’s progress daily – it’s a natural process that doesn’t happen immediately. Instead, measure the progress once a week. The progress will be more noticeable and dramatic than if you check daily. Within a few weeks or so, your copper sink will darken. 

It might not perfectly match the surrounding patina, but it won’t be nearly as noticeable. This method is often the best, especially if you’re unsure how to handle the restoration process. 

Use Ammonia And Salt

Ammonia

If your copper sink is unsealed and has a green patina, use ammonia and salt to restore it. Here’s what you’ll need:

  • Non-iodized salt
  • Clear, detergent-free ammonia
  • White vinegar
  • Clean, lint-free rag
  • Grease cutting mild dish soap
  • Spray bottle

Start by cleaning the sink’s surface to remove any grease or residue. Use grease-cutting mild dish soap and a soft cloth to clean the surface. After you clean the sink, mix the darkening solution. 

In a spray bottle, combine two parts white vinegar, 0.5 parts non-iodized salt, and 1.5 parts clear, detergent-free ammonia. Mix the solution until the salt dissolves, then spray the shiny areas with the solution. 

Allow the solution to sit for one hour, then reapply it to areas that you missed. Allow the patina to dry until it becomes a green, powdery finish. Don’t scrub the powder off, as this is the patina, and it will set permanently in time. Let the sink sit unused overnight. 

Use Baking Soda And Water

Baking Soda

If your sink has a brown patina, use baking soda and hot water to darken the surface. Here’s what you’ll need:

  • Grease-cutting mild dish soap
  • Clean, soft rag
  • Baking soda
  • Hot water
  • Spray bottle
  • Cotton swabs

Start by cleaning the sink’s surface with dish soap and a soft rag. Then, combine baking soda and hot water in a spray bottle. Continue adding baking soda until it will no longer dissolve. Spray the discolored areas with the darkening solution. 

For hard-to-reach areas, use a cotton swab dampened with the solution. Let the solution sit for an hour, then reapply as necessary. This solution won’t powder like the green patina solution, but allow the solution to sit for a while to achieve the brown, coppery finish. 

Use Liver Of Sulfur

Liver of sulfur is another way to darken your copper sink quickly. Keep in mind that this material is poisonous if inhaled (dry lump) and can be a fire hazard (it is flammable). Ensure you wear the proper protective gear, including respiratory gear, goggles, masks, and fully covering clothing. 

Liver of sulfur is readily available online in dry lump and gel forms. It doesn’t have a very long shelf life, so use it shortly after receiving it. 

Here’s what you’ll need:

  • Grease-cutting mild dish soap
  • Liver of sulfur (dry lump or gel)
  • Clean, soft rag
  • Protective gear

Start by cleaning the sink’s surface with grease-cutting dish soap and a soft rag. Once the surface is clean and dry, apply liver of sulfur to create oxidation on the shiny areas. Note that this will cause the copper to turn black quickly and deeply. You may need to use thinned applications to achieve the finish you want. 

Sinkology K2010-BD66 Adams Farmhouse/Apron-Front 33 in. Double Bowl Grid, Drains, and Care Kitchen Sink Kit, 33 inch, Antique Copper

Once you finish applying the liver of sulfur, wipe the surface clean and dry with a clean, soft rag. Dispose of the liver of sulfur according to the instructions – you cannot simply throw it in the trash.  

Warnings 

  • Dry lump liver of sulfur is poisonous when inhaled, so proceed with caution when working with it. 
  • These methods may not work well on copper-plated sinks. If you’re unsure whether your sink is solid copper, check if it’s magnetic. Magnets shouldn’t react with copper, so your sink may be copper-plated if it does. 
  • Always wear the proper protective gear – gloves, respiratory gear (masks), goggles, and clothing. These products may cause adverse reactions if they come into contact with your skin and eyes or are inhaled.