There are several types of bricks . And I assume you are referring to clay bricks. Factory made and hand made. I am talking of Factory made bricks.These should small enough to be handled conveniently approx size 8x4x2. For buildings factory bricks are recommended. The perforated bricks are lighter and easier to handle, and have thermal properties different from solid bricks. The cut bricks are hardened by drying for between 20 and 40 hours at 50-150 C before being fired. The heat for drying is often waste heat from the kiln.
Your vote on this answer has already been received
It should not absorb water.
It should not wither or break when we scratch it with our hand.
Its edges should be even and same, for use with other bricks during construction.
Must be porous enough to grip cement.