TL;DR: Bennu/Ryugu Water Assessment is a main entry in the 外星矿物知识引擎 database.
Direct sample analysis from both missions confirmed phyllosilicate minerals containing structurally bound water. This represents a validated water resource that can be extracted by heating to 300-800°C.
Resource
Hydrated minerals (bound water)
Assessment Method
Sample return analysis (OSIRIS-REx, Hayabusa2), orbital spectroscopy
Estimated Value
5-10% water by mass extractable at moderate temperatures