I just looked into best practice for archival CD and the word seems to be Taiyo Yuden Made in Japan gold CDs.
These are commonly available branded as Maxell CD-R PRO (make sure they are the "PRO" type). Make sure they say "Made in Japan"--but all Maxell CD-R Pros I've seen are Japanese manufacture.
They are only marginally more expensive than the low grade junk, i.e. spindle of 25 for $15.
I had several hundred CDs commercially duplicated about a year and a half ago and, even though stored under reasonable conditions, 50-60% of them have developed read errors.
Hope this helps,
Joe Roberts
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