Impervious Ships (spoilers RWC)

[Farseer]

Could it be made from memory sand/stone harvested from an island like other's island? or perhaps the dead stone dragon on that island althea skinned seals alive on? (according to some observers, lightly embellished)

Most assuredly from either of these, and more.

Re the name of that latter island is The Barrens. I have to stop myself now otherwise I will have to go on and on and on, and here is not the spot for that going on and on and on...but I do love that dragon, and that arrow, and that place, and how it all does or doesn't, or may or may not, fit into the history of the entire realm....not to mention the events of TM. I have raised it ina few spots previously but will have to let that conversation live again one day...

Convoluted interconnections? Yes, please!