What is the preferred material for interleaving silver gelatin photographs in portfolios?
(To be clear, I'm not stacking photos on top of one another. I'm looking to face each photo with a slip/sheet of material to protect the image.)

Would the Unbuffered Tissue from Gaylord be the best? (passed PAT)

http://www.gaylord.com/Preservation/...%29/p/HYB01351

Dartek was recommended to me. What are your thoughts?

Thanks for your help!!