Who does not acknowledge you brought them back? What quest?
Those particular gems are not associated with any quest that I know of.

Windows 7 pro 64 bit
EVGA X58 motherboard
6GB of OCZ DDR3 memory
watercoooled i7 920 @ 3.8GHz (4+4 cores)
EVGA (Nvidia) GTX 275 graphics
Creative X-fi elite pro sound card.