The monk pebbles from the Isle of Mara are not addable to the currency tab. I can somewhat understand this because you don't actually open a merchant window to spend them, but it would be nice to clear them out of my bank. Either that or let them stack to 1000 or something, a 100 stack of items that you need up to 700 of for a title is annoying. Though since the Maj'Dul coins are treated as currency and are turned in the same way, it seems like it would be reasonable to expect the same of the pebbles.