Find a nice grunge texture... I'll use this for an example:
You want a nice contrasting image to use as a mask.
I desaturated the texture and use levels to come up with this:
You can then use the texture as a mask...
- Select and copy the texture image
- Add a mask to the layer you want to add the texture to
- alt+click the mask to edit the mask
- Click on the layer thumbnail again to finish editing the mask.
Have a solid color background layer (=brown here) and in another layer your ball shape. Ball body must be white or at least different than the background, the black part and the exterior must have been cut off (=transparent).
Add a layer mask. Let it at first be full white (=all visible). Paint to it some grey or black to make some transparency, add grain, apply artistic filters to erode the painted patterns.
You may get the wanted result fast by inserting an photo of stone or rost to the layer mask. Layer mask is available for full editing and pasting by clicking the mask icon in the layers panel and holding alt at the same time.
Here's one result from my quite random mask:
If you are not happy with the result, fill the mask with white and try again.
BTW. The ball shape was here assembled in Illustrator and copied to Photoshop via the clipboard.