Glossary

One of the fundamental characteristics of natural-finish porcelain stoneware is its high resistance to abrasion, meaning the ceramic surface’s resistance to wear caused by contact with the heels of shoes, the feet of furniture, chairs, trolleys, vehicles and even floor cleaning equipment. Due to porcelain stoneware’s outstanding resistance to abrasion, the surface does not wear, so there is no change in its shine or colour, and there are also no care problems.

Technique also used for the creation of floor and wall tiles, which produces a three-dimensional effect using textures with different levels, similar to those found in natural materials like stone or wood. Ceramica del Conca uses a state-of-the-art technology called Dinamika that ensures perfect matching between the graphic design and the tile’s structure, achieving an extremely realistic bas-relief effect, as if the surface had been shaped by time and natural erosion.

A bullnose, normally in the same material as the floor tiles and with the same graphic design, is a vertical tile applied to the wall and covering the first 6/10 cm of its height. A bullnose is defined as a trim and has many function, first and foremost concealing the movement joints around the edge of the floor to allow normal expansion of the tiles. It also protects the wall from knocks by shoes or furniture and possible wear-marks left by brushes or vacuum cleaners. A skirting tile may have a rounded or right-angled top edge.

Ceramics have been known to man since prehistory and are inorganic materials, normally made by mixing clays, feldspars, sands and water. Before firing, the mixture is malleable and ductile. Once the mix has been fired, at a temperature varying between 700 °C and 1400 °C, it is fixed in the required shape and becomes rigid and very hard-wearing. There are various types of ceramics: with low porosity, such as stoneware and porcelains, and porous, such as majolicas and terracotta.

Ceramics of Italy is quality mark registered in 2009 by Confindustria Ceramica, the Association that represents, connects, informs and assists Italian producers of ceramic tiles, refractory materials, sanitary ware, tableware and ceramics for industrial use. The quality mark is intended to safeguard all Italian ceramics manufactured in Italy and its connotations extend beyond the strictly geographical, since Made in Italy status implies values such as quality, design, innovation and environmental sustainability, with which Italian products in all fields are associated worldwide. Ceramics of Italy embodies all these values combined with the manufacture of ceramic floor and wall tiles.

Decorative tiles or decors are tiles with particularly varied colouring or attractive graphic design which can beautify and add personality to an entire interior. They may be in different shapes from the tiles in the same collection and from the background tiles, and may also be in multiple colour shades. Decors may be abstract, geometrical or floral, contemporary or in vintage style. Decorative tiles also often have different finishes from the background tile collection, to enable highlighting of a specific area during the architectural design phase, or to evoke impressions of the past or of far-away cultures.

In the inkjet digital method of printing ceramic tiles, a jet of ink is sprayed straight onto the surface of the tile. The introduction of this technology around 2005 revolutionised the ceramic and porcelain stoneware world by enabling the very realistic reproduction of any graphic effect, with vast customisation potentials.

In the winter months, moisture and low temperatures may be a serious threat to an outdoor paving if it does not have effective drainage. Good quality porcelain stoneware is frostproof because it has excellent resistance to low temperatures: as it is not porous, it absorbs an extremely low percentage of water. Thanks to this characteristic, a stoneware paving can withstand the lowest temperatures with no risk of tile detachment or cracking. 

This is a vitreous inorganic coating which may be matt, white or coloured; it may also consist only of unfired porcelain and vitro-porcelain raw materials. It is fired together with the tile body in the single-firing process, at from 1250 °C to 1400 °C. Otherwise, it may comprise a mixture of suspending agent raw materials and frits, for firing at lower temperatures generally around 900 °C.
A ceramic glaze consists of three basic ingredients: the vitrifying substance, the flux and the stabiliser. The glaze forms the actual surface of the tile and establishes its tactile character. There are different types of glaze, including honing glazes, outdoor glazes which contain grits or carborundum and matt glazes.

Glossy is the term used to describe a particularly shiny glazed ceramic or porcelain stoneware tile surface, able to provide a mirror-like reflection. Interior design trends change over time, but glossiness has always been the key characteristic of particularly elegant, prestige surfaces, although not necessarily in the form of a large-size tile or slab. The glossy brick tile is never out of fashion and is used both in design schemes with an artisanal flavour and in commercial or office buildings.

After tiles’ installation, to complete the surface the joints must be filled with a cement-based material, the grout. This protects floor and wall coverings against infiltrations of dirt and liquids of various kinds. Nowadays there is a wide choice of grouts and also of colours for anyone wishing to use the joint to reinforce the aesthetic impact of the ceramic surface.

Ceramic materials have excellent hardness and strength values. The hardness of a ceramic tile or slab is expressed as a number which refers to a mineral included on the Mohs scale. The higher the number, the greater the hardness of the corresponding mineral. Natural finish porcelain stoneware has hardness >6 and as high as 8 points on the Mohs scale, equivalent to that of a gemstone such as topaz. This explains why stoneware tiles are so resistant to scratching.

Installation or laying is the process in which tiles are fixed to the substrate using a suitable adhesive. To ensure a durable, attractive result, floor tiles must be installed by the correct procedure and using good quality products. Before installing the floor, the installation pattern must be decided: the most common layouts are straight or diagonal, running-bond or staggered.

The joint is the gap, from a few to many millimetres in size, left between one tile and the next during installation to enable normal expansion of the floor covering. This prevents cracking and breakage over the years due to structural and thermal settling of various kinds. Wider joints are used, also for reasons of appearance, for rustic floor coverings or brickwork tiles.

Mosaic is a form of decoration practised since ancient times: many mosaics brought to light by archaeological digs are considered to be priceless artworks. Highly prized for their beauty since time immemorial, today mosaics can be produced in porcelain stoneware and consist of mesh or sheets on which small chips of tile are assembled, glued and combined. Chips may be monochrome or in a variety of colours. In general, all floor and wall tile collections include one or more mosaics, to extend the options available to interior designers. Their aesthetic value is still very high and the inclusion of mosaic in an interior is considered to denote luxury and attention to detail. A Mosaic is produced by assembling chips obtained by cutting up tiles, so all their intrinsic and extrinsic characteristics are maintained. Today, any one mosaic may contain chips with different effects or colours, for the creation of more modulated, exquisite wall panels or for designing carpet looks on floors. What’s more, mesh-backed mosaics can cover curved surfaces such as pillars or seats.

Movement joints in floor coverings are created using special strips which absorb thermal expansion, structural settling, dynamic stresses and traffic vibration, preventing cracks in the flooring or paving. Their use is essential because, by acting as dampers, they are crucial in ensuring the quality and duration of the materials installed.

A tile is classified as “porcelain stoneware” on the basis of its water absorption characteristics (<0.5%). This material’s minimal absorption implies a very low porosity and the complete fusion of the tile body, making this material very similar to a glass. Porcelain stoneware tiles are produced by mixing various raw and other materials which are first milled and then spray-dried prior to pressing.

The grade is the marking applied to every lot of tiles which defines its quality. Boxes are marked with the number 1 for first grade material. First grade material is regulated by standards which set appearance, physical and mechanical parameters which must be exceeded for the award of this classification. Tiles which fail to meet these requirements are downgraded to second or third grade, depending on the severity of the defect found.

In this process, the edges of tiles are trimmed so that they are perfectly straight and perpendicular.
Whether or not a tile’s edges have been rectified is a very important factor to be checked at the time of purchase if the intention is to install the material with narrow joints and create a continuous, resin-effect stoneware ceramic surface. With rectified edges, joints as narrow as 2 mm are permissible.

Shade variation is the term used when the surface of a tile is intentionally not uniform in colour and tone. These variations in colour within the same tile collection are used to reproduce textures that evoke natural materials such as stone or marble. In the case of a wood effect, shade variation can provide a distressed, time-worn appearance.

The size refers both to the shape of the tile, which may be square, rectangular, hexagonal or irregular, and the dimensions of the sides, on which basis tiles are classified as small, medium and large size. In general, tiles over 120 cm are defined as large size tiles or ceramic slabs. When choosing the most suitable size, consideration must be given to the type of location, the size of the interior, whether or not there is natural light, its intended use and the desired style.

Normally, when tiles are over 120 cm in size they are defined as ceramic slabs. Apart from their size and appearance, the installation method is also different from that used for smaller tiles. The installation of slabs requires special care, with the use of specific equipment, the right adhesive and the correct adhesive application procedure. Porcelain stoneware slabs are particularly attractive and are being more and more widely used in architectural and interior design projects and in locations where continuity between the floor and wall covering or between different rooms is required.

There are different degrees of slip resistance and different methods for measuring it. The most widely used method is a German test, which awards an R value. The lowest value is R9 and the highest is R13. A higher anti-slip resistance coefficient is obtained during production by adding abrasive particles to the surface glaze, or by the creation of relief textures or ribbing.

In physics, friction is defined as a force opposing the movement of an object in relation to its contact surface. If the object is not moving in relation to the surface, friction is static; if the object is moving in relation to the surface, friction is dynamic. In ceramics, and for floor tiles in particular, the friction coefficient is used as a parameter for assessing tiles’ anti-slip capabilities.

Static friction coefficients are classified as follows:
≤ 0.50: Dangerously slippery
0.50 – 0-60: Satisfactory grip
≥ 0.60: Anti-slip

Dynamic friction coefficients are mainly tested using the Italian BCRA standard and the American standard, although the new EN 16165 standard APPENDIX B is considered the most widely used standard in Europe. Its classification is as follows:
R9: Normal grip – from 3° to 10°
R10: Medium grip – from 10° to 19°
R11: High grip – from 19° to 27°
R12: Strong grip – from 27° to 35°
R13: Very strong grip – gradient over 35°

Stoneware objects (pottery to contain food or water) dating from about eighteen thousand years ago have been found in the Middle East. Today, the main objects industrially produced in stoneware are floor and wall tiles. Porcelain stoneware, a particularly compact ceramic material, is widely used in contexts of all kinds, due to its countless mechanical, functional and aesthetic qualities: very low water absorption; resistance to abrasion; resistance to foot traffic, wear and time; resistance to chemical and weather; compactness, versatility and very high aesthetic impact.

Tiles’ surface finish is produced by a variety of different processes depending on the appearance required.
The natural finish, for example, is the most widely used and the most versatile.
The shine finish, on the other hand, is produced by honing the ceramic surface to create a luxurious “mirror” effect. It is often used on ceramic slabs for a particularly glossy, glassy surface, and to increase their impression of depth.

Through-body porcelain stoneware is a type of stoneware in which the surface colours are the same throughout the entire tile.
This means that even if the tile is chipped, a very rare occurrence in good quality products, the damage in terms of appearance is minimal, because there is no difference between the surface and the part underneath.

The tone is the colour shade of a specific production batch of tiles. In the production process, it is virtually impossible to produce pieces that are perfectly identical in terms of colour. Therefore,
before packaging tiles are grouped by colour shade and assigned an alphanumerical code which identifies their specific tone. 

The trims in ceramic collections are porcelain stoneware pieces of different shapes designed to meet all architects’ needs. They normally comprise bull-nose and curb tiles, skirting tiles, steps and sills, but the Ceramica del Conca outdoor collection also features a wealth of trims for swimming-pool areas, such as hand-grip edge tiles, coping tiles for low walls with non-drip edges, gratings with custom finishes, bench seat surfaces and also articles for gardens and urban areas such as flower tubs or bicycle racks.

Tiles’ working size is marked on the packaging and is an important parameter for their correct installation. Tiles leaving the kiln may vary in size by a few millimetres, giving them different working sizes, so during grading they are placed in lots of the same size, within the tolerances set by the standards.