I’m far from an expert, but anything on standards JIS X6257 / ISO 18630 would probably be a good start. It’s an open standard for 100+ year discs.

Otherwise probably best to look into accelerated aging studies. For technology that’s less that 100 yrs old to claim 100 or 1000 is a bit uncertain but accelerated aging is probably the closest to a best guess. I recall skimming over a third party lab saying Verbatim gold foil archival DVDs were estimated to last 30-120 years depending on storage methods and luck, but never saved the link.

Oh yeah, stick it in the sun or a damp box and either will probably be bad in weeks instead of decades or centuries. But supposedly they’ll meet those lifespans good at room temp

Kinda funny, I was just writing about archival media this morning. Verbatim makes DVDs & Blue Rays that last ~100 years, and M-DISC makes ones that’ll last ~1000 years. And the Verbatim Blu Rays run ~$0.036 per gig.