From the publisher:
Eighty Pages of Power!
Magic rings in d20 System games are often temporary tools. A player character gets a ring of protection, uses it for a few levels, then sells it off when a better one comes along. But wouldn't you like your character to have truly important artifacts like you find in novels?
Artifacts of the Ages: Rings gives player characters a reason to hang on to their arcane jewelry. The legendary rings, gems, and jewlery found in this book are powerful enough to be useful at high levels, but they start as minor magic items, and gain in power as the campaign progresses, so the GM can introduce them to his campaign while the characters are still low-level. These artifacts increase in power as the possessors advance in level.
The artifacts in Rings, offer minor powers to any wearer, but grant their better abilities to those wearers who take one of the scion classes. The wearer unlocks new abilities of the item by advancing in its associated prestige class. In short, the prestige classes reward the player for keeping a magic item.
Artifacts of the Ages: Rings, the third PDF in the Artifacts of the Ages Series, shows you how to ensure that magic items in your campaign have the possibility to be the treasured possession of a lifetime for the right character.