I would like to leave each of my boys a small portfolio of prints, in theory identical, that will remain unchanged in their lifetime. Originally I was thinking more along the lines of their kids and grandkids lifespans, with the portfolios divided up down the generations. But in the next 50 years (the boys are 21), other things might become more important than saving bulky non-survival-related items. And grandkids are unlikely, but not out of the question. So just in case, I'll mat up my well-processed platinum prints and carbon prints 'archivally', put them in good boxes and know that they have the potential to last a few hundred years without significant change.
This will be one of the images...Three Boys, Redwood, 2003, 8x10 Platinum/palladium from in-camera negative