Metric Convertion

Need help converting tile sizes from millimetres to inches? Click here to download a helpful conversion chart.

Tile Terminology

Crackle Glaze: Special glaze effect featuring fine cracks and an “antique” look.

Dust or Dry Pressed Tile: An efficient and cost-effective method where tiles are made from a powdered or small-grained mass that is then formed in high-pressure molds. Dry-pressed tile is more dimensionally consistent.

Efflorescence: Tile decorated with colored clays, then fired. Also, colored tiles forming a pattern in a wall or floor.

Extruded Tile: Soft clay is forced through an extruder and the continuous ribbon of clay, formed to the desired shape, is then cut into individual tiles. Extruded tile includes rustic styles such as terra cotta and clinker. This process results in a less even tile and enhances the hand-formed look. The molding process also allows for trim pieces to be matched to a coordinating field tile.

Full Glaze Polished / Lapatto: Identical in nature to the terms polished and semi-polished that describe techniques used on unglazed tile. On glazed tile, full polish is achieved by highly polishing the entire surface. Lapatto (partial polish) is the effect on a textured surface when high areas of the glaze are polished and low areas do not.

Impervious Tile: Tile with a water absorption rating of 0.5% or lower. Ideal for submersion (pools and fountains), high foot and vehicular traffic.

Majolica: Formerly, earthenware with an opaque luster glaze and over-glaze colored decorations. Currently describes any decorated earthenware with an opaque glaze.

Non-vitreous Tile: Water absorption level above 7%. For walls and hand traffic only.

PEI: Porcelain Enamel Institute – the U.S. entity responsible for research, testing and analysis of ceramic materials.

Picket: A rectangular tile pointed at the narrow ends, which may be used to create an intricate border.

Porcelain: A ceramic material made by heating refined materials, often including clay in the form of kaolinite, to high temperatures in a kiln at temperatures between 1,200 °C(2,192 °F) and 1,400 °C (2,552 °F). The toughness, strength, and translucence of porcelain arise mainly from the formation at these high temperatures of glass and the mineral mullite within the fired body.

Rectified Tile: Tile, glazed or unglazed is cut on all sides (usually with water-jet technology) after its final firing. This ensures that each tile is identical in size and caliber (for setting with minimum joint width) and eliminates the pressed (pillowed) edge, making the tile completely flat. For large installations, eliminating the curved edge creates the effect of a single, seamless slab, as light is reflected evenly across the entire surface.

Red Body Tile: Tile made from red-colored raw materials. The tile is coated with an opaque layer of engobe to conceal its natural coloration, before glazes are applied.

Semi-vitreous: Tile with a water absorption level of 3-7%. For dry, interior spaces, normal foot traffic.

Soldier Course: Oblong tile laid with the long side vertical and all joints aligned.

Tumbled Tile: Unglazed and glazed material is mechanically or chemically altered, using various processes, to create a rustic, antiquated or distressed surface.

Vitreous Tile: Water absorption of 0.5%-3.0%. Interior, exterior, occasionally wet areas.

Vitrification: The progressive reduction in porosity of a ceramic composition as a result of heat treatment or another process.

White Body Tile: Tile composed of raw materials producing a white tile body that can be coated with a transparent glaze and takes color easily. Normally used for wall tiles.

Get in touch

We love clean design and advanced digital solutions.

Find a Company

Search Tile of Spain Manufacturers for direct contacts


For more about Spanish tile, media inquiries or image requests


Receive the Tile of Spain Connection — monthly inspiration and trends