Henri is finally able to show Number Four its function once he develops his first legacy (Lumen). In the centre, the size of an orange, is the Sun of Lorien's solar system and it also shows Lorien the way it is now, a barren wasteland. However when Henri blows on it or Four shines his Lumen on the planet, it transforms and it shows what Lorien looked like before the Mogadorian Invasion. (I Am Number Four).
It is later revealed that the glass orbs are somehow linked with the Red Crystal, on the way to Paradise with Six, Sam and Bernie Kosar to search Sam's back yard, Four looks at the solar system, which transforms into the globe of Earth and he can see Marina's position in Spain as well as hearing her shouting Adelina's name (after opening her chest in the belfry). (The Power of Six)
After leaving the Mogadorian Mountain Base, Four and Nine sift through their chests and Four removes the glass orbs once again, showing them to Nine. Suddenly, they rearrange into the globe of Earth once again and they can see their own positions, (sat with their chests open), a dot in India, signifying Marina's open chest, along with shouting and chaos (as Six, Marina, Crayton and Ella are attacked). They also see a dot travelling fast through Brazil, suggesting that Number Five had a Crystal compass of his own. (The Rise of Nine).