How to tell Ceramic from Porcelain.

Both porcelain and ceramic tiles are made from a mixture of clay and other materials which are pressed into a dense mass then kiln-fired at over 1000 degrees C. Although both porcelain and ceramic tiles are called “ceramic tile”, porcelain is by definition harder, denser and absorbs less water which is why it is less prone to cracking when exposed to cold. Specifically porcelain should absorb less than 0,5% of its volume in water. But how do you tell whether a tile is porcelain or ordinary ceramic? 1. Check the packaging. Look for the word “Porcelain”, a water absorption of <0,5% or a Mohs hardness rating of 7 or above. Ceramic tiles generally only have a water absorption of <3% at best. If the tile is marked ‘Polished’ it is likely to be porcelain. 2. Check the price. Porcelain tiles usually cost around 40% more than ordinary ceramic tiles and could be even higher depending on other technical factors. 3. Try the spit test for water absorption. Turn the tile on it’s side. Apply a little spittle to the edge. If it is absorbed into the tile within a minute or less it’s ceramic. On a porcelain tile the liquid will remain on the surface in a shiny meniscus for many minutes or even until it evaporates Porcelain tiles are generally made by the dust pressed method from porcelain clay like kaolin, which result in a tile that is denser and more durable than ceramic tile. The finish is a finer grained and smoother with sharply formed faces. Glazed porcelain tiles are much harder and are more wear and damage resistant than non-porcelain ceramic tiles. 4. Take a close look. Full body porcelain tiles carry the color and pattern through the entire thickness of the tile making them virtually impervious to wear and are suitable for any application. If the colour on the surface is the same through the cross section it is a good but not infallible indication that you are looking at a porcelain tile. 5. Compare the hardness. Ceramic tiles are softer and easier to cut than porcelain so if you are comparing two tiles the one that is easier to cut is probably ceramic. 6. Test the hardness. A more accurate way would be to actually test the hardness using a reference material. Hardness is measured using the Mohs scale which rates hardness from 1 (talc) to 10 (diamond). Ordinary ceramic tiles will have a hardness of 5-6 whereas porcelain will have a hardness of 7 or better. You can use the following commonly available materials to firmly scratch the tile. If the material leaves a distinct mark the tile has a hardness less than the test material · Penny (a bronze coin) - 3.0 · Knife blade (a good straight edged kitchen knife or penknife) - 5.0 · Glass (a broken piece of window glass) - 5.5 · Quartz (a sharp piece, available at new age lifestyle shops or a mineral scratch patch) - 7.0 ...and lastly 7. Contact the manufacturer and request a laboratory test report. Porcelain is classed B1a with a water absorption of <0,5% For any other inquiries about Porcelain or Ceramic tiles please drop us an email.   Ciao, The Link International team.