I recently received one half (one valve) of a Tridacna gigas as a gift from
     my aunt.  According to her, she purchased it from a local fisherman in
     Hawaii back in the 1970s.  The thing is about 15 inches long by 11 inches
     wide and weighs over 15 pounds.  She had a time bringing it back to L.A.
     since she couldn't check it with the luggage and had to hand carry it onto
     the plane.  Well she was younger and stronger back then.

     Anyway, can anyone tell me if Tridacna gigas was found in Hawaiian waters
     back then or at anytime.

     Thanks.

     Ted from Los Angeles.