"You have found a way of restoring the vis absorption properties to crystals. By combining eight of these crystals you can create a crystal capacitor that functions in much the same way as infused ore.
Each crystal capacitor can store up to 100 vis and will slowly absorb or release vis if nearby nodes are above or below their baseline levels. It can only absorb or release 1 vis every 5 seconds.
The capacitor can be safely moved without losing any stored vis." Here's a video that shows you how Crystal Clusters and Crystal Capacitors work: