Why Your Copper Sink Keeps Tarnishing (And How to Stop It)
AN EVERBRITE GUIDE
By Everbrite Coatings, makers of ProtectaClear and CrobialCoat. Protecting and restoring metal since 1990. 6 minute read
5 reasons it keeps tarnishing, and what owners do instead of polishing it every week.
Before you spend another Saturday polishing, or price-out a new sink, here is why the shine never lasts and the step that keeps it tarnish-free.
One copper sink owner summed it up in a comment on a home decorating blog: her sink looks beautiful for about five minutes, until someone runs the water.
If that sounds like your kitchen, you are in good company. A copper sink is one of the most beautiful things you can put in a house, and one of the hardest to keep looking good.
Nothing is wrong with your sink or with the way you clean it. Bare copper reacts with almost everything it touches, and most of the usual fixes clean it without protecting it. So the clock starts again the moment you put the cloth away.
Does your sink do this?
Water spots around the faucet soon after you dry it
Black drips running down the sides toward the drain
Green and black stains that come back after every scrub
Bright spots where lemon or tomato sat for a minute
A shine that is gone a few days after you polish
What most owners try first
Polishing every week
Wax after cleaning
Lemon and salt, vinegar or ketchup
Tarn-X and a lot of scrubbing
Spray paint
Each of these helps for a day or a week. Here is why none of them lasts, and what the owners who stopped polishing did instead.
01
Copper reacts with water, food and hands
Tarnish is the copper reacting with whatever touches it. Our page on fingerprints explains it this way: "Fingerprints and smudges are caused by acids, oils, and salts on your hands." A sink gets all of that, plus water, soap, coffee and acidic food, many times a day. Acid is why a slice of lemon or a tomato leaves a bright spot on a darker sink. Water and its minerals add to it, and the black stains tend to show up where water runs and dries.
02
Polishing resets the clock
Polish takes the tarnish off and leaves bright, bare copper behind. That bare copper starts reacting again with the next rinse and the next hand on the faucet. So a sink that looks perfect on Saturday is spotted by midweek, and the only way to keep up is to polish again.
Why fresh polish tarnishes fastest
"Freshly cleaned and polished copper is especially sensitive to fingerprints." The oils and salts from a hand make the copper "oxidize or tarnish at a faster rate in the areas touched, forming a dark layer of copper compounds." That dark layer is the thumbprint you find later.
"After using another brand of copper polish weekly for about a year, just to have the sink continue to tarnish, I was ready to get rid of the sink. I hated the constant maintenance."
Jaqlynn P. Miles, TX, farmhouse copper sink
03
Wax wears off, and home remedies leave acid behind
Wax sits on top of the copper and washes away a little with every use. One owner on a metal-finishing forum said waxing her sink after cleaning didn’t slow the discoloring at all.
Lemon and salt, vinegar and ketchup do clean copper, because they are acids. We tested several of these recipes on a piece of copper, and the difference after an hour amazed us. The trouble comes later. Clean copper "will tarnish quickly unless protected," and acid left on the metal can darken it under a coating unless you neutralize it first. Rinsing with water does not take it all off.
04
Paint and a new sink trade one problem for another
When polishing wears people out, paint is often the next idea. Julie Fiato of Redhead Can Decorate tried spray painting her copper sink, and it didn’t last. She replaced the sink after that, and she still wasn’t happy with it. Replacing a sink can also mean cutting into the countertop, which is why one of her readers said she wanted to rip hers out but couldn’t face the countertop work.
05
What keeps the shine is a clear coat on clean copper
Each fix above deals with tarnish after it forms. A clear protective coating keeps water, food, skin oils and air off the copper, so the look you have today stays put. For a sink it has to be thin, hard and clear, so you still see hammered copper, and it has to go on clean metal. You choose the look first, polished bright or a dark patina you like, and then you seal it.
Try this first
Our FAQ gives the test for bare copper: "Clean or polish a small spot. If the shine returns, our coatings will lock in that look and prevent future tarnish."
What we make specifically for sinks
Pick the kit that fits your sink
Every option uses CrobialCoat, our ProtectaClear coating with added antimicrobial technology. The different choices depends on how much cleaning your sink needs first.
New sink, or a patina you want to keep: CrobialCoat Only
Wash, dry and wipe with a clean solvent, then coat the sink as it is. The coating locks in the finish you have now. From $29.95 Get CrobialCoat
Light tarnish: Sink Kit with Polish
Once you clean your sink, polish with the Midas Touch polish included in this kit. It has no acid, so nothing needs neutralizing. Wash off any polish residue, dry and wipe with a clean solvent. Then seal in the shine. 4 oz kit $44.95, pint kit $75.95 See Sink Kits with Polish
Heavy tarnish, old patina to remove, or an intricate design: Sink Kit with Gel and Polish
HD Copper Cleaning Gel clings to the sides of the sink and gets into detailed designs. The kit’s EZ-Prep neutralizes it before you polish, solvent wipe and seal.
4 oz kit $62.95, pint kit $94.95 See Sink Kits with Gel
Not sure which one you need? Compare all three options on our Sinks page, or call us at 800-304-0566.
All products are made and shipped in the USA. We only charge the actual cost of shipping, with no handling fees.
What the job looks like
Most of the work is cleaning the sink. Plan an afternoon for multiple coats and at least a few days of careful use while it cures. Complete step-by-step instructions come with every order.
If your sink is new or you're keeping the patina, skip the cleaning and start with wash, rinse and dry.
Clean to the look you want
Light tarnish: Polish with the Midas Touch polish in the kit until the sink looks the way you want it to stay. It has no acid, so there’s nothing to neutralize.
Heavy tarnish or an old patina: Spread the HD Copper Cleaning Gel on the sink and give it time to work. It clings to the sides and gets into detailed designs. When the tarnish lifts, wipe off the gel or wash it down. Then wash the sink with the EZ-Prep in the kit to neutralize the acid in the gel, and polish with Midas Touch to the sheen you want.
If you cleaned with lemon, vinegar or another acid cleaner before using the kit, neutralize with EZ-Prep or baking soda and water as well.
Wash, rinse and dry
A few drops of dish soap take off the black polish residue. Rinse with plain water and dry it completely. A hair dryer helps speed drying around the drain and the faucet, where water hides.
Wipe with clean solvent
Wipe the copper with a clean solvent so no oils or polish residue are left on it.
Glide on 2 to 4 thin coats
Let each coat dry for at least an hour. Glide the applicator on with light pressure, and walk away to leave a drying coat alone. CrobialCoat self levels as it dries so trust the process and give it time.
Let it cure for 4 to 5 days
The coating is delicate until it is fully cured. That takes at least 4 to 5 days, and it can take longer in a deep sink or in cool, damp weather. Until it’s cured, dry the sink with a soft cloth after every use, and never leave standing water in it. Warm, circulating air from a fan or a heater helps it cure faster.
An honest note
This is a coating, and coatings wear. A kitchen sink gets used many times a day, so it will need a fresh coat sooner than a copper lamp would. Our FAQ says it plainly: "copper sinks or counter-tops will need more frequent applications than lamps." On a kitchen sink, expect it to last about 12 to 18 months. When yours starts to look dull, remove the old coating with a clean solvent like xylene and apply a fresh one. It comes off easily, and you start again with clean copper. Watch how easy it is to redo
The usual fixes, side by side
What each one does well, and the catch.
Method | What it does well | The catch |
Polishing every week | Brings the shine back the same day | Leaves bare copper that starts to tarnish again right away |
Wax | Cheap and quick | Washes off, and owners say it doesn’t slow the discoloring |
Lemon, vinegar or ketchup | Cleans tarnish with things already in the kitchen | They are acids, and clean copper but it will tarnish quickly unless protected |
Paint | Covers the stains | Covers the copper too, and often doesn’t last |
A new sink | A fresh start | A new copper sink is expensive, is also bare copper, and the counter may need cutting |
Clear protective coating | Keeps the polished finish or the patina you like, and is tarnish resistant with antimicrobial properties. | Takes an afternoon plus at least 4 to 5 days to cure, and lasts about 12-18 months on a busy kitchen sink |
From owners who stopped polishing
Copper farmhouse sink · CrobialCoat
"I was AMAZED at the results with CrobialCoat. I love my new sink and tell everyone who will listen about how it was restored. Thanks to CrobialCoat, my sink is now one of my favorite parts of my kitchen."
Jaqlynn P. Miles, TX
Copper sink · ProtectaClear kit
"Got the ProtectaClear kit to fix our copper sink. The only way it could have been easier is to have someone else to do it. It has been on for about a month and still looks great. Thanks for saving me $1000.00."
Horace S., Mt Pleasant SC
Copper farmhouse sink · ProtectaClear kit
"We have a lovely copper farmers sink in our kitchen and had to constantly clean it. No sooner was it cleaned, when it would start to turn again, even with no water being run! We searched online and found your advertisement. We got the ProtectaClear kit about a month ago, and truthfully thought the instructions were a bit overwhelming, so we kept putting off the project. Last weekend we decided to roll up our sleeves and get it done. We were pleasantly surprised at how easy the process was!! Our sink turned out just beautiful!!! We are so pleased with the results!!! We would highly recommend ProtectaClear!!"
Mike S., Darlington MD
Brass powder room sink · ProtectaClear
"We were about to replace this $800 sink because the maintenance was so tedious but your product saved us the cost and problem of doing that. We had tried everything, nothing worked. Now the decorative sink in our powder room sparkles and is virtually maintenance-free. I do not have to rush in to polish it each time a guest uses it."
Barbara and Leigh B.
Copper sink coating: common questions
Will it look plastic or too shiny?
No. ProtectaClear, the coating CrobialCoat is built on, is made to be "practically invisible even on mirror-polished surfaces" and the coat is thin, so you still see the copper and its hammered texture.
Can I keep the dark patina on my sink?
Yes. Wash it with a few drops of dish soap, rinse, dry and wipe it with a clean solvent, then coat it as it is. The coating locks in the color you have now and prevents bright stains from acid based foods.
Is it safe on a kitchen sink?
Yes. Once it has fully cured, the coating is food-safe and skin-safe. Curing takes at least 4 to 5 days and sometimes longer if the sink is deep or in cool, damp weather. Until then the coating is delicate, so dry the sink after each use and don’t let water sit in it. Warm, circulating air helps it cure faster. Because a kitchen sink gets so much use, plan to redo the coating about every 12 to 18 months.
Why can't I buy it at the hardware store?
To keep costs down and provide expert support for our specialized products, we don't sell in retail stores. We make Everbrite, ProtectaClear and CrobialCoat in the USA and sell them directly to customers. We charge only the actual cost of shipping, with no handling fees. If you have questions, please call us and real people answer the phone. We are available Monday to Friday, 8am to 5pm Pacific. 800-304-0566
Keep the sink you fell in love with
You don’t need a new sink to get the one you wanted back. Whether yours is brand new, darkened to a patina you like, or covered in tarnish, the last step is the same: get it to the look you want, then seal it. Every rinse after that runs off a clear coat instead of bare copper.
Not sure where yours falls? Polish one small spot. If the shine comes back easily, the Sink Kit with Polish is enough. If it doesn’t, start with the gel.
Questions about your sink? Call us, we're real people: 800-304-0566, Monday to Friday, 8am to 5pm Pacific.
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