Perhaps you mean platinum cobalt magnets instead of platinum AlNiCo. Back in the late 50's - 60's the Pt Co magnets would have had the highest energy product and coercivity of any magnet of the time, besting the more pedestrian aluminum nickel cobalt (AlNiCo) iron magnets. The 70's saw the advent of neodymium iron boron and samarium cobalt magnets where the neo magnets are the current kings of the hill.
I can't help you with the lineage of Pt Co magnets at Koetsu, but they certainly could have been a sexy choice decades back.
Brock
I can't help you with the lineage of Pt Co magnets at Koetsu, but they certainly could have been a sexy choice decades back.
Brock