The process is relatively straight forward. All concrete is placed in a wet and malleable state (often referred to as the Plastic State). This property of concrete enables it to be formed into an endless number of shapes.
Over a period of hours, the concrete ceases to be Plastic, and begins to firm and become hard (often referred to as the Hardened State).
Before final set of the surface occurs, the top few millimetres of concrete are removed in order to reveal the materials embedded within it.
The surface paste can be removed in a number of ways, but the most common is to wash the surface material away with pressurised water.
Chemicals called Surface Retardants help to keep the surface paste soft and help to ensure an even exposure of the underlying stone is ultimately achieved.
This process of revealing, or exposing the stone (normally called: aggregate) is why the resulting finish is called: Exposed Aggregate Concrete.