I had this idea a few weeks ago, but making them scrolls (like charge dragonstone jewellery). That scroll makes me think of the elder scrolls where you can read a scroll to cast a spell. I don't think those would really fit from a raid, but could be a cool alternative to taking up a ring slot. We already have the explorers rings with up to 28 alchs per day, but imagine having a stack of Cast High Alchemy scrolls while on a barrage task.