How to fade / scatter sand on the floor around? I am trying to scatter sand so it fades out better onto the floor around it.
This is what I have know:

And this is what I want it to kind look like:

Any help or suggestions would be greatly appreciated.
Thanks
You could use the image you show as a stencil to create a black and white image texture:

Then use this image texture as a mask in a material that mixes your background with a noisy material: