Currently the info for this page resides on the Chain-Gang site.
for an excellent explanation of galvanic corrosion
and why we use sacrificial anodes made of magnesium in rivers
to avoid buying expensive propellors made of bronze or brass.
the fore-going link is to a PDF prepared and published by Trent Boats
A company that takes this trouble is a company I can do business with
and I wish to publicly acknowledge that consideration.