A large magnet or
compass will tell you if it is iron or lead, but I'd agree with hellosailor about it being encapsulated. Definitely get a good survey with a competent surveyor that has experience with GRP sailboats.
Only difference is that a lead keel will denser and the boat will be a bit more stable, given the same size (volume) keels, as a lead keel will be a greater percentage of the boat's displacement than a equal size iron keel. If the keels are the same weight, a lead keel will be smaller, and produce a bit less drag than the same boat with an iron keel of equal weight/mass.
__________________
Sailingdog
Telstar 28
New England
You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.
—Cpt. Mal Reynolds, Serenity (edited)
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