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Microsoft develops ultra durable glass plates that can store several TBs of data for 10000 years
(unlocked.microsoft.com)
This is a most excellent place for technology news and articles.
Article says the glass plates can only be written once, so don't toss out your hdd just yet
They could replace WORM storage, and since the person you responded to mentioned LTO, WORM may be possible with their data set since LTO is traditionally used for backups