Edit: The ships were old at the outbreak of WWII, but were not slow. Voyager had a top speed of 34 knots and Stuart a very fast 36.5.
WIPO ASSIGNS PATENT TO SUMITOMO METAL INDUSTRIES FOR "METHOD FOR SEPARATING AND RECOVERING ELEMENTS COEXISTING IN SCRAP IRON" (JAPANESE INVENTORS)
Dec 31, 2010; GENEVA, Dec. 31 -- Publication No. WO/2010/150873 was published on Dec. 29. Title of the invention: "METHOD FOR SEPARATING AND...