Now that you have scanned rifts you are probably wondering how to close these to stop them from getting out of control. Luckily there is a way but the infusion recipe has Very High Instability, the basic idea behind this is to blow the rift up so it closes:
Crafting these and throwing them into a rift will cause it to close very quickly but the rift will also drop Void Seeds:
Scan these and collect them, these will be used later on. Rifts also have a chance of Dropping Primordial Pearls but this chance is very low, there is about a 1 in 6 chance one could drop from a very large rift. These pearls have a durability of 9 and can not be repaired, they do not stack but are very much needed later on.