I just finished an onyx backsplash in a kitchen with backlit slab onyx countertops. The countertops are solid honey onyx slabs with built-in LED lighting beneath them. The backsplash is 12 x 12 honey onyx tile installed on-point (diagonally).
Although onyx looks great when installed it is a very difficult stone to work with. Onyx is made up of bands of silicon dioxide, commonly known as quartz crystals, which fuse together into layers of translucent stone. This leads to varying striations of color and transparency throughout the stone. While cutting or fabricating bullnose (rounded) edges the stone is fairly brittle and has a tendency to literally shatter like glass. The most important tool to own while working with onyx is patience.
After letting the stone set overnight so the mortar could cure I grouted the backsplash with C-Cure brand “Macadamia” unsanded grout. Never use sanded grout with onyx or other fragile stones such as polished marble, the sand in the grout will scratch the surface of the stone. The grout will lighten as it cures and matches the base color of the stone almost perfectly. The grout lines will nearly disappear after the grout cures.
If you need an onyx installer in Fort Collins or Northern Colorado just give us a call. You may click on any of the photos below for a full-size version.
{ 4 comments… read them below or add one }
I love this website. The onyx back lighting idea is spectacular !
My husband and I know that we want an onyx backspash for our kitchen. However, we were worried that amber onyx would be too soft for our countertops and instead were thinking of a granite countertop or even porcelian due to the hardness of the material. We were curious if you have seen a granite that looked great with amber onyx. If so, which granite (s) ? (Right now we were thinking of a slab of golden butterfly that is really rather orange and brown. And, we were looking at a slab of golden oak granite (brown like oak). Our cabinents are beige. We also have wood trim at the very top and a brown busy mosaic tile floor. Thanks for any advice !
Hi Roxanne,
Thank you for the kind words!
The look really depends on your particular taste. Some people lean more toward a contrasting color scheme and some toward a complimenting.
The golden butterfly, in my opinion, would end up really orange with a honey or amber onyx backsplash. The golden oak would look good. You may also want to take a look at colombo gold, madura gold, or calypso gold granites. Any of them would compliment a honey or amber onyx backsplash.
Hope that helps.
I installed 5/8 onyx backsplash and I am having problems with the grout. The onyx is golden, but when we grout it turns dirty brown. Do you have any suggestions on what to use?
I am thinking about using clear caulk.
Thanks
Mike
Hi Mike,
The problem you are having is due to the light transmission through the sides of the tile. When you add grout, of any color, you will considerably diminish the amount of light entering into the individual tile. Since onyx, especially honey onyx, is highly translucent removing any of the light will mute the natural color. To maintain the color of the stone you want to allow as much light transmission as possible through the sides of the stone.
Clear caulk is an alternative but I would not use it. It will still mute the stone’s translucence to an extent and caulk is not made, nor recommended, for that application. Think about the clear bead of silicone in a shower or bathtub. Once the airtight seal of the two materials (such as the tile and acrylic of the tub) is broken and moisture gets behind it, this leads to mold and all types of unsavory things you don’t want in your kitchen backsplash.
The two alternatives that I have used are either a regular epoxy, the two part glue, that cures clear, or what is called “knife grade” liquid polyester. The latter can be found at a specialty art store and places such as that. It is used in casting and fabrication processes. Hope that helps.