So between volume 1 and Khriss' entry in Arcanum, we know that the sand mastery works by using water to create a connection to the lichen on the sand on Taldain's Dayside. This causes the sand to turn black until it recharges under the sun's investiture.
So simple question: would it even work on other worlds? Is it something that maybe could manipulate invested matter (like god metals and stormlight filled gems)? Or is it something that is useless outside of Taldain?