It's not pitted, it's made from compressing metal powder into shape and then fused by heat, a process called sintering. The pitting is the gaps left between the powder particles, very useful for oil retention.
Kommando is correct the material used for fork bushes is oilite which is a form of sintered self lubricating bronze all those lovely holes retain lube for smooth operation
they do look a little crude but still possibly the best material for application