Riko took it on her journey, but quickly lost it in the first layer when she got excited and it slipped out of her hand while she was shaking it. It hasn't been seen since.
Vueko inherited one from her caretaker, and then used it to traverse the sea to find the abyss with Ganja. She gave it to the island natives in an exchange. Whether Riko's compass is the same one as Vueko's is unknown.
Riko's theory that it points to the bottom is backed up by the fact that while in the hands of Vueko, it always pointed towards the abyss even when she was far away from it.