Did the Battle of Iwo Jima really happen on black soil?

Question

In Flags of Our Fathers, there are whole war scenes shot on black soil near some sea.

Did the Battle of Iwo Jima really happen on black soil or was this added by the movie production crew?

Answer 1

Did the Battle of Iwo Jima really happen on black soil

Yes

Iwo Jima is an island of the Japanese Volcano Islands chain south of the Ogasawara Islands and together with them form the Ogasawara Archipelago also known as the Bonin Islands and does, indeed, have volcanic black sand on it's beaches where the Marines landed.

It's actually volcanic rock ash rather than burned organic material.

^{Src: Wikipedia}