Path of Exile 3.6: Item Synthesis Guide
(N4G PC)

In Synthesis, both the new kind of items and the new way of creating items are intricately related. The former is whats known as Fractured Items, which are items that have fractured modifiers, these are modifiers that cannot be changed by POE Orbs or any other POE Currency. These fractured items can be obtained in memory zones in Acts and memories in the Memory Nexus. While they can be used by themselves, their ultimate purpose is to be ingredients in this leagues eponymous process: Synthesis. This is performed by combining three fractured items, with the resulting item known as a synthesized item.