This is a paid asset, but now you can download Ore Veins for FREE, but please remember this package is provided only for learning purposes or to be able to test before buying the product, NOT FOR COMMERCIAL PURPOSES.
Detail this asset from Unity Store: Original Link
Ore Veins v2.0
All models have been completely revamped.
Twelve low poly ore veins. Six large veins, and six small: copper, tin, iron, silver, gold, and mythril.
The two rocks come as separate meshes, so after the ore is mined, a bare rock can be left behind. (You can, of course, remove the whole vein instead, if you’d prefer :)).
All models share the same diffuse texture, normalmap, and material. Prefabs included.
View screenshots bellow.
Total vertices: 1962
Total tris: 3204
Texture: Diffuse 1024 by 1024 png
Texture: Normalmap 1024 by 1024 png