The refraction is trickin' ya, jspine. Makes it look like it's only half a bivalve. If it were really an abalone, it would have to be a sinistral one. (I've never heard of a left-handed abalone, although they might exist.) Anyway, it's not an abalone. The hairy-looking things around the edge of the abalone are part of the animal, the hairy ones on the clam are part of the periostracum.
Cheers,
Don