Onyx countertops require special care to retain their beauty. Onyx must be sealed upon installation and re-sealed at regular intervals, and should be polished occasionally. If there are spills, the stone should be cleaned immediately using a special formula cleaner. With proper care, your onyx will last for years.

Getting onyx countertops is a little bit like getting a puppy. They both require frequent care, and you have to be ready to clean up any mess ASAP! I can’t help you with the dog, but I can tell you how to take care of your onyx.

white onyx countertops in kitchen

It’s not easy to keep your kitchen this bright and white!

Step 1: Sealing your onyx countertop.

Step #1 is to use a special sealer on your countertop to maintain its luminous shine and make the most of its durability. It’s best to have this done by a professional since it’s so critical.

Generally, whoever installs onyx will also seal it, but you have to be careful with other contractors. Onyx is still rare and some people will mistakenly think they can seal onyx just because they know how to work with granite (a much harder and more durable stone).

If you choose to do the sealing yourself, the most important thing to do is get the right sealer.

If you can afford onyx countertops, you can afford the proper sealer. Don’t just run to the local hardware store (or worse, WalMart) and find an ordinary stone sealer. The easiest thing to do is use whatever your stone supplier recommends.

If that doesn’t help, look into MB Stone Granite Sealer MB-4. MB Stone is a well-regarded company. Conveniently, the full kit you’d need for sealing and polishing your stone countertops is available here.

Another premium product with a good reputation is Aquamix Sealers Choice Gold. This stuff is about $100 for a gallon, which is enough to seal multiple counter tops.

If you need to look up more products, try to find a fluorocarbon alphatic resin-based impregnator sealer. Silicone-based products are not as ideal for onyx.

Re-sealing onyx

Most onyx needs re-sealed every 1-3 years. How often you seal your onyx depends on how much the surface gets used, what types of cleaner you use it on, and the color. A lighter colored onyx, like the popular white onyx, will need sealed more often since it stains more easily.

Again, your stone supplier should be able to tell you how often to seal (and in some cases, if the onyx should even be sealed in the first place).

Step 2: Cleaning your onyx countertop.

On a daily basis, you should watch for any reason to clean your onyx countertop.

Since onyx is soft and calcium-based, it will react with acids. Not just chemistry lab acids, but common household liquids such as vinegar, lemon juice, coffee, and yes, red wine!

So, do NOT use any homemade cleaners, glass/window cleaner, or normal kitchen countertop cleaners, as these could be too acidic.

Likewise, do not use abrasive cleaners. That’s really the #1 rule here. Most countertop cleaners are indeed too harsh and acidic for onyx.

Instead, use natural cleaning products with a neutral pH and a soft cloth. Gel Gloss is sometimes recommended (and easy to find; it’s $16 on Amazon).

Or ask your stone supplier – they should know the best cleaner for their stone and might sell it themselves.

Tip: Use the cleaner applied to a soft cloth. Don’t put the cleaner directly on the counter top as the onyx may absorb too much of it, doing more harm than good.

In case of spills…

Step 3: Blot up spills immediately.

Onyx is naturally porous and will absorb liquids. So, clean up spills immediately. Rather than wiping, blot up the liquid with a paper towel.

Spills are especially dangerous is if it’s an acidic liquid, because the “acid etch” that happens can really dull your stone.

Despite popular belief, sealers don’t actually prevent stains. They just give you a little bit more time before the stone absorbs what gets spilled on it! So be vigilant about cleaning.

How to polish onyx countertops.

To recap, here is a step-by-step guide to clean and polish your onyx countertops to keep them in good shape.

  1. Seal the surface. Use a special stone sealer, such as MB Stone Granite Sealer or Aquamix Sealers Choice Gold, on the onyx to help prevent acid etching and staining.
  2. Clean with a soft cloth and special cleaner. Apply a special cleaner, such as Gel Gloss, to a soft cloth and then wipe it on the onyx surface.
  3. Blot up spills immediately. Blot up any spills using a paper towel. Do not wipe or apply pressure.

If you seal your onyx countertops as often as necessary and clean up any spills, you should have many years of enjoyment!