many layers of ply and glass mat laminated with epoxy.
Just for fun, here's what it replaced.
That mess actually kept the mast standing for a trip by the PO from Santa Monica to San Rafael.
Something that hasn't been mentioned is to change the shoe from a cup the mast sits inside to a cruciform base that sits inside the mast.
I had to build a new step for my Columbia 43 and did it like this;
Due to the corrosion from the existing cup style step the foot of the mast needed to be...