Travertine

Travertine, which is essentially a sort of limestone, is a naturally occurring rock available for extraction in quarries worldwide. Its geological location strongly influences its appearance and properties, from colour to overall strength. While travertine is not as sturdy as granite, it’s more refined in character and suitable for many applications. Travertine stone blocks can be processed with the assistance of channelling machines, wire saws, chainsaws, and water-jet cutting. Sliced into stone slabs of a specific thickness, it can be surface-treated, cut into tiles, and managed further. 

• Travertine flooring
• Travertine paving
• Accent and feature walls
• Fireplaces
• Stone benchtops
• Travertine countertops and basins
• Facades 

Travertine features no specific subtypes; rather, it’s distinguished by quality grades and cut type. The two main types of travertine tiles in New Zealand are determined by the cutting methods used and do not represent different varieties of stone.

There are three essential grades of travertine. 

• Third grade: Commercial grade, with visible imperfections and the surface appearance of traditional limestone. It rarely features uniform thickness or neat cut, while the amount of filler used inside is moderate to high. Edges might be cracked. Substantial colour variations are possible, including black or grey marks. Small defects in sizing and honing and large voids stuffed with filler are also often found in this category. 

• Second grade: Standard grade can be perfectly cut with a uniform thickness, but the filler content is still large. Minor holes are allowed and may be filled, but the edges are smooth, well-cut, and uniform. The colour palette is extensive, while the shade is consistent and free from discolouration or visible marks. 

• First grade: Premium level is a perfectly cut piece of travertine stone with uniform thickness and minimal filler content. Slabs and tiles are double-filled, perfected manually, with edges perfectly cut, smooth and evenly sized. The largest colour selection is available at this level, consistent and free of imperfections.

The structure of travertine makes it possible to produce different effects with various cut types. Two essential cuts for creating travertine tiles are the fleuri cut and vein cut.

• Fleuri cut: A cross-cut made parallel to the bedding plane to showcase the structure with a typically circular pattern. While the fleuri cut delivers a sturdy tile, it also may produce some holes, making it unsuitable for use as a flooring tile in high-traffic areas.

• Vein cut: Slicing along the veins earned this cut’s name. Rather than the parallel, the vein cut goes right through the bedding planes, exposing the edge. These travertine tiles are recognised by a linear pattern. 

The third factor for differentiating travertine slabs and tiles is the finish. 

• Tumbled: A rough, unique look created by tumbling travertine pieces in a barrel filled with water and abrasive materials. This process can take up to five weeks, during which it creates a moderately even finish on all pieces. Tumbled travertine is traditionally left unfilled. It's suitable for application in showers, spas, tubs and wet spaces, due to its anti-slip properties. Other uses include kitchen backsplashes and outdoor applications. 

• Honed: Smooth finish with an organic appearance is slightly less rustic than tumbled travertine. In the honing process, one side of the slab or tile is ground down with variable grit materials, producing a range of surfaces. Those can be both filled and unfilled. Honed travertine can be matte, satin or boast a high sheen, still applicable in wet environments. Other uses include indoor flooring and walling, kitchen backsplashes, outdoor installations, and swimming pool areas.

• Polished: A glossy surface similar to polished marble is suitable for a range of designs and decor styles, from traditional to modern. Similarly to the honing process, polishing includes grounding the stone with grit abrasive products until the desired level of shine is achieved. Filling delivers a uniform look while using sealants on top of filled travertine results in very high glossiness. Polished travertine is fit for both outdoor and indoor use, but it should be avoided in the flooring of wet areas such as showers.

It’s important to recognise good quality travertine tiles before buying. The corners should be uniformly cut at 90 degrees with perpendicular side cuts and no slopes. The colour should be consistent, with no rust markings, and the surface smooth with no visible pores in the hard resin filling of the stone. The natural shades of travertine range from pale cream, ivory and beige, to rich golden hues, rustic reds, and deep mochas. Silver travertine is a popular choice for modern environments and commercial applications in New Zealand. Limestone is prevalently organic but can also be obtained in the form of an engineered stone.