As one would except, pre-existing material got sucked into this new world.

The concert will feature these new works, as well as pre-existing material.

Vanadinite is an uncommon mineral, only occurring as the result of chemical alterations to a pre-existing material.

The longer ones show signs of having been assembled from pre-existing disparate materials.

"Then the youth market returned, and for the younger generation there really was no pre-existing material," he said.

I find that commonality in working with pre-existing materials.

Composition is one of the most important features of graphic design especially when using pre-existing materials or diverse elements.

Most of them are based on pre-existing material, but some are entirely original creations.

From what pre-existing material was it produced (analysis)?

Not all shared universe settings are simply the expansion or combination of pre-existing material by new authors.