The Healing Brush Tool makes it easy to clone visually complicated areas.
The photograph above is a good example of a subject with a fairly
complicated surface. Using the Clone Stamp tool would have made it quite
difficult to paint over the cracked areas while retaining the integrity of the
stained stone. Much of the discoloration would have been sacrificed as you
sourced smoother areas to erase the cracks. However, the Healing Brush
was able to effectively replace the cracked areas with smoother areas, while
sampling from the surrounding area to replicate the stains.