I think people are getting confused about this. ALL Piezography inks have incredible longevity, though Carbon is the best since it's pure carbon, all the other Piezography ink tones will still outlive any of us and them some. Certainly, we believe in using the best materials and methods for both storing and displaying artwork, though UV protection and museum quality glass isn't necessary with Piezography prints, it is better than regular glass.
Consider where and how long your prints will be displayed: bright window light, or dim room light, displayed temporarily for an exhibition, then on a wall if someone buys it, or stored away if it's not bought. How many years do people display the same artwork, or do decorations such as art get moved or replaced every few years? Obviously every piece of art gets a different life after leaving it's creator, but you can rest assured that prints made with any Piezography ink tone will last a VERY VERY long time.
I hope this helps.
Best regards and happy printing~ Dana