Okay, i've been leveling up in the Ozmone Plain for a while, trying to get my levels high enough so I don't killed by Redmaws and Seekers in the Henne Mines..again, and occassionally, i'll steal/find a dropped item called 'Gemini Gem' or 'Aries Gem' etc.

Do this items hold any value, like pertaining to the Espers and they'd be useful later on, or are they just Loot?

I really need to know because I always sell them in Jahara.