Plaster is not a naturally occurring substance. It's made from materials that are found in nature, but it's the processed and manufactured form of those materials.

Here's where the raw materials for plaster come from:

* Gypsum: This is the main ingredient in most plasters. Gypsum is a naturally occurring mineral found in sedimentary rocks. It's mined from quarries around the world.

* Lime: Some plasters also use lime, which is produced by heating limestone (calcium carbonate) until it decomposes into calcium oxide. Limestone is another naturally occurring rock found in many places.

So, while plaster itself isn't "found" in a raw state, the ingredients for plaster are found in quarries and mines all over the world.