DIO's Bone

The term DIO's Bone (DIOの骨) refers to a bone belonging to DIO, entrusted to Enrico Pucci before the events of Stone Ocean.

Appearance
The bone's particular shape and the presence of two round eminences (corresponding to the so-called sesamoid bones) indicate that it's DIO's first metatarsal bone, i.e. one of the bones within the foot behind the big toe.

History
Sometime in 1988, DIO asked Pucci if he will someday betray him due to him having the power to take The World any time he wanted with Whitesnake. Pucci explained that he loves DIO as he loves God, and that he never thought of taking his Stand. DIO apologized for insulting him and handed him a bone that he ripped out of his own body as a token.

Years later during the events of Stone Ocean, Pucci enlists Sports Maxx's power to bring it back to life, the bone becomes infectious. Anyone who touched it would mutate, slowly germinating until becoming a sort of plant.

Once turned into plants, the nutrients they absorb from sunlight were given to a baby-like creature referred to as DIO 's homunculus, or the Green Baby. Upon the birth of the Green Baby, a part of DIO's soul was reborn into it.

36 convicts of Green Dolphin Street Prison were mutated by the bone, and the nutrients they absorbed from sunlight eventually formed a baby-like creature referred to as the Green Baby.

This Green baby then sought out Pucci, and upon finding him, fused with his Stand in order to create C-Moon.

Trivia

 * It should be noted that even though it is considered DIO's bone, it is actually a bone from the body of Jonathan Joestar, whose body he stole, replacing Jonathan's head with his own head, at the end of Phantom Blood.
 * According to the rules established in Part 3, it is because of this that the Green Baby, and later on Enrico Pucci and his twin brother Weather Report each receive the Star Birthmark on the back of their necks.