Download Noise Blend Free Unity.
A surface shader that uses noise to blend two textures on a surface.
This lets you create effects like rust patches, dirt areas, overgrown brick work and much more. You can use the base texture’s brightness to control where the overlay texture is placed – letting you create effects such as mould growing along the mortar between bricks or gaps between stones.
The shaders are for either Opaque or Transparent and either simple Lambert (diffuse) or Specular lighting including reflection.