Comparable to stone poe currency from mtnba2k's blog

Comparable to stone, a range of "elder uniques" were poe currency added in War for the Atlas that can simply fall from The Elder himself. Game Designer Hrishi took some time to Go over the Cyclopean Coil, Blasphemer's Grasp, Nebuloch, Hopeshredder, Shimmeron, Impresence and Watcher's Eye. Each has its own distinct market in Path of Exile, both in terms of its unique appearance, but also in terms of what it increases the overall player experience through attribute focus, ailment focus and a whole lot more.

[T]he unique items needed to be made in this way that made them generally helpful for a wide variety of builds, and to make a reason to keep fighting the Elder many times, or the items would feel as though they had no worth.

The general design of a lot of elder uniques is that they're intended for a big variety of builds. As a result of this, the attention on poe marketplace those designs are characteristics, ailments, charges, curses and auras.