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Are these platters too ? Do they pay a different rate ?
How would I clean them?

Not sure what I'm looking at. Almost looks like disk canisters from a mainframe or mini?

If they are then no, not platters but as to what you'll get from anyone is totally up to each buyer.
If they're actually still sealed try ebay for the best price.

assuming they are canister disks...
Old canister disks are an entirely different technology than the hard drive disk. The entire writing mechanism is inside the canister.
The disks will be one of two things depending on the method of writing. Nickel platters with a thick! Ferrite, cobalt, or hematite layer. Data is written by removing magnetic blocks, not adding. And you're looking at something like cobalt recovery rates or dirty nickel, either way 2-4 dollars a pound for the raw disks.

Or it will be inverted recording (like modern disks) and have aluminium or silver platters with a very thin palladium or gold micro-coating.
In the gold breakage category at around 30ish a pound either way.
In all cases for the value for the platters themselves.

BUT if the seals are intact (meaning the vacuum is still intact) they can fetch much more to a parts buyer. Sealed ones can be clean room refurbished /repaired, and there are still many many old server minis in use. $100-500+ for them. Try Hard Drive Buyers Inc on silk road as well.

I have vax 6000 servers . Not sure about what was stated in response but I will post the disks uncovered.. Till then.......Thanks 1scrap.

Additional pictures

Ah. Disc pack. From the late 60s-70s.
Technically they're hard drive platters. Not sure about what boardsort would say. I've never had one in person so I'm only passingly familiar