Join Date: Feb 2000
Location: Annapolis, Md
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I am not sure that there is the only one answer but traditionally cast iron was considered stronger in a grounding. That is partially offset by Lead''s ductility which can absorb impact energy rather than distribute directly into the hull.
While iron rusts and needs to be refaired periodically, adhesion between lead and fairing materials can be poor as well and so refairing of a lead keel can be as frequent as iron.
These days Europe has tighter occupational hazzard and environmental laws as pertains to lead so that lead is proportionately more expensive in the EU.