I noticed an eBay ad for a 1964 Supraphonic on ebay asking $900. Search eBay for "1964 Ludwig" and you'll see it. Wait? $900?? So I read the ad further. In the description he references his thread on VDF from 2011 stating that a refrigerator magnet will stick to the shell. The link to this thread is below.
Now, I have a complete and original 1964 Supra. The serial number is less than 1000 away from the one on eBay. The shell is in near mint condition without a mark on it. I tried the fridge magnet and it stuck. I used a name badge (rare earth) magnet and it will jump off of the table about 1/4" and attach itself to the shell. I have 2 Acrolites ('64 and '78)and the magnets will not stick.
Do I believe for an instant that I have a "Unicorn" steel shelled Supra? Nope.
Am I curious? Yes!
I am not a metallurgist. I would logically surmise that the magnetic attraction, the close production/serial numbers, and the amazing condition of the shells could point towards a shell "batch" ferrous metal content anomaly, or a plating material or process different from what they have used since.
2011 thread referenced on eBay
http://www.vintagedrumforum.com/showthread.php?t=25918
Thoughts?