Stone veneer can me made from natural stone as well as manufactured stone.
Natural stone veneer is made from real stone, the stone is cut to a consistent thickness and weight for use as a veneer.
Manufactured stone veneer is either fabricated by pouring a lightweight concrete mix into forms and then painted with a coloring process which makes it resemble real stone. Or flexible stone veneer is created by pulling a thin layer of stone from a slab of slate, sandstone, or mica schist. It is backed by a composite material.
The advantages of manufactured stone veneer over natural stone are:
Cost (cost of material, cost of application, waste cost)
Weight (ease and cost of application)
Variety of designs and colors
Manufactured veneer is cheaper than natural stone, approximately 1/3 to 1/2 the cost of natural stone. Its light weight eliminates the need for wall ties or footings and make it easier and cheaper to build. Furthermore, manufactured stone veneer has a significantly smaller waste factor than natural stone. The variety of designs and colors makes available options which would not be available with natural stone, since natural stone is used in the general area around the locality which it is extracted.