Adam Bjerk
How to Clean Copper
Copper’s beauty, versatility, and durability have made it a highly valued metal for the past sixty centuries. A piece of ancient copper jewelry found in modern day Iraq dates back to around 9,000 BC – the very dawn of civilization. Copper jewelry is still fashioned to this day, but the metal’s unique properties make it useful for much more. Copper is great conductor of heat. As a result, copper pots and cookware are highly valued by chefs around the world. Copper is also a great conductor of electricity and it’s extremely malleable, lending its use to wiring, plumbing, and technology. Copper coins and currency, art and architecture all speak to the metal’s unique beauty.
The sheer volume of uses for this metal leaves people confused when it comes to copper cleaning. The good news is, whether you want to clean copper pots, jewelry, art, or a copper roof, the same principles apply: you need a slight acid and a fine abrasive. However, you may not want to clean copper at all. When it is exposed to air over time, copper tarnishes (oxidizes). This can give it a caramel, antique look preferred by some collectors. When copper is exposed to outdoor acids and other elements, it develops a thin blue-green hue called a “patina”, as on the Statue of Liberty. Patinas take years to form and some pay large sums of money to try to hurry this process through chemical treatments. Perhaps you like the bright, peach and pink radiance of clean copper. Perhaps you’re just cleaning copper pots or countertops. Whatever your goal is, I’ll show you how to clean copper using safe, non-toxic items you already have in your home.
How to Clean Copper at Home
Before starting, see if what you are cleaning is actually copper and if it is protected by lacquer. If a magnet sticks to your item, the copper is plated over another metal. If the magnet falls limp, you’re dealing with copper. If you can’t tell if the item has a protective lacquer coating (modern decorative items all do), dab white vinegar mixed with a touch of baking soda (dilutes the acid) in an inconspicuous area (not with expensive antiques). If the copper cleans or brightens immediately, there is no lacquer.
Wash the copper in warm water with a splash of gentle dish soap. This helps to clean copper of mineral deposits and loose debris. If your copper item is protected by a lacquered finish, or it is copper plated, don’t put it in the sink. Just use a damp rag with a touch of soap to clean your item and dry thoroughly – you are now finished. If your item is free of lacquer, let it soak for a bit (10 minutes), and then clean it with a soft rag. Normally this is all you would do too, but I’m guessing you also want to de-tarnish that copper and make it shine, so keep reading.
If you want to get rid of the lacquer finish on your copper, boil it with baking soda. Damaged or cracked lacquer causes copper to age unevenly and become ashamed of itself. Again, some people just lust for that mesmerizing copper glow, and must strip the lacquer to polish the metal. Boil the copper for thirty minutes with one tablespoon of baking soda for each quart of water needed. Large items may need to be boiled in sections, which is laborious. Hardware stores sell lacquer removers, and acetone will also work. But these are harsh chemicals – a far cry from water and baking soda.
Now make your copper cleaning and polishing potion. Ok, “potion” may be a bit strong (and odd) but this stuff works. Create a thick paste using salt, white vinegar, and flour. Exact measurements aren’t necessary, but I went heavy on the flour to keep the paste less abrasive. Glop the paste on the copper and let it sit for 10 minutes to an hour depending on the severity of the tarnish. Then, using a soft cloth, briefly yet briskly polish the copper, going with the grain if possible. You may need a soft-bristled toothbrush or cotton swab to clean the finer details.
Rinse the copper item and dry thoroughly. Copper straight up hates water. If not dried with enthusiasm, it tends to boast ridiculous water marks. It’s like an elegant tuxedo with roller blades and a codpiece. When finished, buff the copper with a fresh soft cloth. Look on as the clean copper glistens – your reflection smiling back at you. The dealer who sold me the pot (antique dealer) would guffaw hard if she could see it now. She preferred the dark, dull “antiqued” look.
If you cleaned copper jewelry or décor, protect your work. If you don’t like the nutty browns and blue-green hues of tarnished or patinaed copper, you can buy a spray-on lacquer at any hardware store; however, lacquer is a hassle, and it cancels out copper’s anti-microbial properties. Many people protect their clean copper with virgin olive oil. Simply rub a thin layer into the piece with a soft cloth. Of course, if you intend to use the newly clean copper for cooking, apply nothing.
More Ways to Clean Copper Naturally
As you can see, the above method for cleaning copper works very well, but it’s not the only way to get the job done. De-tarnishing copper requires a slight acid and a slight abrasive. Below you’ll find more effective ways to clean copper without purchasing expensive, harsh chemicals.
Sliced lemon and salt to clean copper pots. This method is ideal for busy kitchens. Slice a lemon in half and dip it in salt and rub it into the bottom of the pot. Lemons are expensive, so don’t waste them. When finished, you could put the lemon down the garbage disposal to keep your sink fresh. (Note: tarnished, dull copper transfers heat just as well as clean copper)
Vinegar and salt saturate to clean sensitive copper jewelry/antiques. Fill a jar with white vinegar and keep adding salt until it no longer dissipates. Clean your copper item with a soft cloth, rinse, and dry thoroughly. Label the jar for later use on any copper or brass.
Ketchup. The person who discovered this copper cleaner was either good at chemistry or completely disturbed. This works much the same way as the salt, flour, and vinegar paste; however, I think robbing French fries of their birthright is wrong. It’s also messy.
Lemon juice, salt, and flour. This is nearly the same cleaner as the one featured above. White vinegar and lemon juice have similar PH levels, but lemon juice is more acidic than most vinegar solutions. Substituting lemon juice for vinegar will give you some added punch to clean copper that is severely tarnished.
How to clean pennies. If you are here to clean copper pennies, follow the link. My friend is an avid coin collector, and he will show you how to do this without damaging your investment.
Eco-Friendly Copper Cleaners
Twinkle Copper Polish. While no commercial metal polish is going to be completely free of earth-killing chemicals, this one has been mentioned in several green publications. It contains no phosphorus and the packaging is recycled cardboard. It is very popular with copper collectors, and they go out of their way to get it - you won’t find Twinkle in stores. There are many online vendors and the price, even with shipping, is very reasonable.
Quickleen. From what I’ve heard from collectors, Quickleen is great for cleaning copper, other metals, and a variety of surfaces. I haven’t come across a website for a metal cleaner that is so hell-bent on coming across as green. They boast that you don’t even have to use gloves while using this product. I wonder, is it also safe to eat?
Bistro Copper and Brass Cleaner. Copper polishers are always boasting how “non-abrasive” they are, as though polishing metal could be anything but an abrasive process. Well, this product uses a super-fine abrasive that will leave your copper with a mirror finish – free of scratches.