I made an item of power and thought I'd add it here for critique.
Eye of the Graeae from [-1] to [-4]
Description: A false eye made of amethyst that grants the user the power to use The Sight. With use, a wielder of the Eye can awaken other powers in it. It is not in fact the actual Eye of the Graeae, but a clever imitation made by a scion of Hephaestus who intended it as a gift to the Grey Sisters, but he was killed before he could give it to them and his killer picked it up. He in turn lost it in a bet with a Sidhe Lady and it has been in the Nevernever since. Even though it is not the original, it conveys various powers of sight on the owner and over time it has acquired some magical power due to its connection to the Grey Witches.
Musts: You must have an aspect related to your possession of this item.
Skills Affected: Lore, Discipline, Alertness, Investigation
Effects:[-0]
It Is What It Is. It's a false eye. Therefore, in order to make use of the Eye of the Graeae, a character must lose an eye and place the Eye of the Graeae in its stead. Like the original, you can use its power even when you hold it in your hand. However, to do this, it needs to be attuned to you by resting in your eye-socket. The eye does not grant standard vision - it is, after all, a false eye - and thus the Aspect associated with this Item will be compelled quite often for situations requiring depth perception or mundane vision, depending on whether your other eye works properly or not.
[-0]
Unbreakable. The Eye of the Graeae, as an Item of Power, cannot be broken except with a magical ritual predicated upon perverting its purpose.
[+1]
One-Time Discount. The Eye of the Graeae is easily concealed. You could pop it out and hide it in you pocket, or you could just keep your eye closed.
[-1]
The Sight. The purpose of the Eye was to help you see, and whatever you see with it is true and real. Needs to be activated, like the normal Sight power.
Upgrades:[-0]
Cassandra's Tears. Because the Eye sees that which is true, it can sometimes see what will be as well as what is.
[-1]
Supernatural Sense. The Eye of the Graeae lets you see magic, as if it were colour or heat. This lets you see auras, tell wizards from mundanes or spirits at a distance by their glow, read the patterns of spell residue and anything else the GM thinks reasonable.
[-3]
Thaumaturgy. The Eye of the Graeae gives you the power to cast spells like a witch.
Notes: The One-Time Discount does not apply until there is at least a -2 cost of powers to link it to.
Thaumaturgy may be bought as Ritual first. If so, it is restricted to something traditionally witchy, like Craft Potion or Enthropomancy.
The Eye does not grant normal vision. You cannot read with it, tell what colour something is nor any number of little things that you need normal non-metaphoric vision to do.
edit: Don't know who the Graeae are?
see here.
edit 2: Modified.