The requirements of good aggregate are as follows.

1. A good aggregate should be strong having sufficient impact, crushing and abrasion strength.

2. A good aggregate should be durable to resist atmospheric variation.

3. It should be non-reactive type to avoid alkali- aggregate reaction.

4. It should be clean i.e. free from organic and inorganic impurities.

5. It should be well graded with minimum voids.

6. It should have rough texture for better bonding.

7. It should not absorb water more than 5%from added water to avoid variation in w/c ratio.

8. It should have angular shape for strong interlocking of particular.