Ceramics & Stoneware
These materials are made from a base of sand and clay and are extremely porous unless a glaze or seal is applied to outer surface during or after manufacture.
They are used for sanitary fitting, tableware and kitchenware. Floor as well as Wall Tiles.
Manufacture:-
- Different proportions and types of clay are mixed with other ingredients
- Shape the article
- The clay is then fired at a high temperature to make it hard
- Glazing is done and article fired for a second time
Following are the types found:
- Earthen ware: is a thick, heavy & very porous material which is usually glazed. Mugs, bowls, vases, ashtray, etc are example. Earthenware chips and breaks easily. It may be glazed or vitrified.
- Glazed earthenware contains a large amount of fine white clay called ball clay. This makes it thick and opaque.
- Vitrified earthenware/ Vitreous China: it is fired at high temperature. It contains more flint/ quartz which makes it very strong but not very heavy. Some may be high chip resistant, used as crockery and sanitary ware.
- Terracotta – made from fine clay baked and mostly left unglazed. It is brownish red in colour. Used for pottery, ashtray, vases and ornamental building materials.
- Stone ware: this has higher stone content. It is fired at higher temperature than earthenware giving a stronger material. It is oven & flame proof.
- Porcelain: this is translucent, containing china clay, china stone / feldspar. It is extremely hard and strong as well as expensive. Used for cups, saucers, etc.
- Bone china: contains bone ash and less feldspar. It is fired at very high temperature making it very thin and strong. Designs are applied to the outer surface and so care should be taken to wash them. It is used to make fine cups, saucers and other types of crockery.
Cleaning & Storing:
- Care should be taken to avoid chipping, scratching, etc.
- Extremes of temperature should be avoided
- Harsh abrasive not to be used
- A hot neutral synthetic detergent solution should be used following by rinsing and drying
- Stains of tea and coffee can be removed by rubbing with a damp cloth and bicarbonate of soda.
Cleaning of ceramic tiles:
- Daily cleaning – wash with general purpose cleaner and dry
- Periodic cleaning – Scrub with a mild abrasive cleaner, rinse and dry.
