Onyx and travertine at home: where they shine and where they struggle
Backlit onyx walls, travertine floors and vanities, and why neither belongs on a busy kitchen worktop. With vein cut and cross cut travertine explained.
By the Ajusteur teamUpdated 3 minute read
Why onyx glows
Onyx is very fine grained and translucent. Honey Onyx from Pakistan runs from pale yellow to honey with darker veins, and with a light behind it the whole slab glows. That is why you see it on bar fronts, reception desks and feature walls.
It is also soft, brittle and very sensitive to acid. Keep it off worktops and floors. On a vanity it needs a resin or mesh backing and a gentle hand.
Source: Brachot: Onyx Miele
How soft is soft?
Onyx and travertine are both calcite, and calcite sits at 3 on the Mohs hardness scale, where a copper coin is 3.5 and a steel knife about 5.5. So a coin scratches them and a knife cuts a line. Quartz, the mineral in quartzite and in engineered quartz tops, is 7. That gap is why onyx stays on walls: a worktop meets keys, pans and grit every day, and a wall meets nothing but light.
A building made of travertine
If you want to see what travertine does at scale, the Getty Center in Los Angeles is built from it. The museum says its 16,000 tons of travertine came from Bagni di Tivoli, 15 miles east of Rome, and cover about 1.2 million square feet. The blocks were split along the natural grain rather than sawn smooth, which is why the walls show the holes and the layers, and visitors are invited to look for fossilised leaves, feathers and branches in the stone.
Tivoli is the same district the Romans quarried, and the same source as the Travertino Romano in our records. Split faced on a wall, honed and filled on a floor, the one stone does two very different jobs.
Source: Getty Center: Architecture
Travertine: vein cut or cross cut?
Travertine forms in layers. Saw the block across the layers, which is called vein cut, and you get parallel bands. Saw it along them, called cross cut, and you get soft beige clouds with no bands. Same stone, two very different floors. Travertino Romano Classico from Tivoli near Rome is sold both ways.
Filled or open holes?
Travertine is full of small holes from the way it formed. For a worktop, vanity or floor they are filled with resin or cement so dirt and water have nowhere to sit. On a wall you can leave them open for texture.
Like marble, travertine is calcite, so acids etch it. It is happy on floors and walls, indoors and out, and needs care on a kitchen worktop.
Where each one works
A quick guide from our stone records.
Planning a wall or a floor?
Both stones turn up most often in renovations rather than kitchens: a lit onyx wall in a majlis, a travertine floor running out to the terrace. Have a look at the stone records, and if the stone is part of a bigger change, start with how we plan a renovation.
Quick questions
Can onyx be used as a kitchen worktop?
It is best avoided. Onyx is soft, brittle and very sensitive to acid. Use it backlit on walls or bar fronts.
What is the difference between vein cut and cross cut travertine?
Vein cut is sawn across the layers and shows parallel bands. Cross cut is sawn along them and shows soft clouds.
Where does travertine come from?
The classic Roman travertine is quarried around Tivoli, east of Rome, the source of the Getty Center's 16,000 tons and of the Travertino Romano in our stone records. Turkey, Iran and Mexico quarry it too.