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I wanted to challenge myself to try to make a shader that utilizes voronoi noise to draw a pile of coins – and this is the result. The main shader which draws this material is made up of a series of layers of coins, which are node groups that can be chained together, along with a base layer that fills in the gaps.
Theoretically, you could do layers and layers of coins all the way down, but I opted not to do it that way, since you can hardly see the difference most of the time anyway.
The coin color is built into the shader/node group, but it can easily be changed by editing the color ramps in the Coin Layer and Coin Base node groups.
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Here’s the same material with the Mask Modifier set to use vertex colors, and some gemstone particles (included in the Blend file).