Original Tele Neck Pickup Magnets

Does anyone know what kind of magnets the original telecaster neck pickups used?

Thanks.

I believe Alnico 3

Thanks. That really helps.

+1 for 3's
Caution: is that there may have been some 5's then, or just that the Factory Invoice read 5's at Leos Shop but somehow 3's were being installed - ,
and there's some sparse info about the metallurgy composition possibly being altered way back then something about the Cobalt content having wide variances ???-

but my gauss meter here has indicated AlNiCo 3's on the 54's and below