You might be interested in the following article from the "National Geographic News" website:
Titanic Bows to Nature
How is that related to Chemistry? Well, Titanic's hull is mostly made of steel, which is an iron alloy, and it is slowly rusting away and being eaten by microorganisms and fungi that feed on iron oxide. The strange formations seen in the pictures, which resemble red icicles, are actually made of rust, and were dubbed "rusticles" by oceanographer Robert Ballard, who lead the team that discovered the wreck of Titanic.
A link to a small article on rusticles found in Wikipedia is here.
