Floor tiles and over burnt brick

Qualities of good floor tiles

1. Uniform shape and size, with true plane surface and sharp edges, and no warping or cracks.
2. Hard, dense and strong, with a smooth, uniform surface and a good colour and finish.
3. High abrasion and wear resistance for foot traffic.
4. Low water absorption (not more than about 3 to 10% depending on type).
5. Good resistance to stains, acids, chemicals and frost.
6. Adequate flexural/breaking strength, and a ringing sound when tapped.
7. Slip resistance on the surface and easy cleaning.
8. Durability and fire resistance, with a low cost.

Properties of over-burnt brick

• Dark brown or blackish colour, with a vitrified (glassy) surface.
• Irregular, distorted, shrunk shape and brittle nature because of fusion.
• Very hard, high crushing strength but low impact resistance.
• Very low water absorption.
• Poor bond with mortar because of the smooth surface.
• Used as aggregate for lime concrete, in foundations and road metal (jhama brick).