What are rusticles? © Getty Images

What are rusticles?

A rusticle is a formation of rust often found on sunken ships - but how are they formed?

Asked by: Marko Wilkinson, Serbia


Rusticles are stalactite-like structures that are formed when iron-loving bacteria attack the steel in sunken ships. These ‘rivers of rust’ run down the sides of the ship (most famously in the case of the Titanic) and contain dozens of microbial species feeding off the iron. Eventually they will destroy it, although estimates vary as to how long this may take.


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