The Question Of Physical Strength

While Lucius could have given the artifact to someone else for them to use, for example to Arius and the others when they return to be utilized when they spy in Tarka barony, it was still probably a prized equipment.

He needed to consider it carefully before just handing it over to someone else.

"The crystal comes from a rare ranked beast, and considering that it's a winged creature that can fly up higher than most… it's no doubt difficult to capture." Lucius said as he glanced at the artifact. "I suppose, it'll be with me until it is to be actually needed." 

Since Lucius had no capacity to make artifacts yet and make use of the rune crystals that he got with him, it was important to keep what artifacts he had with himself.

They might be able to save his life or give him the edge that he needed in a situation.