IBM Disk Platter: I am selling one of two from my personal collection! I have owned it since 1977 and it was given to me from a computer engineer friend.I was told it may be from the 350 IBM series (1960's)or similar machine.One of the viewers says it is not from the 350,so indeed it might be special for the military and one more viewer said it is from a Burroughs computer. I believe  there are only a few left in the world. What is rare about this platter is that it is gold plated and most definitely been designed for the military. All other platters were oxide coated.It is also has been recently x-rayed. Gold plated, slight platinum, Nickel and the base is copper. The bad news it has some tarnish and oxidation. You may or may not be able to rub it out. Approx 26 3/4" x 1/8"thick and about 35 lbs.A must for a museum/university or collector. And finally it is sold as is, no official paper work or documentation. No returns.Check out the link.......