I Need An Evil Object (I Need Your Help!)

I am putting this post in several places- my other author blog, on facebook on my regular profile page and on my author profile page and here on goodreads where all the avid readers gather-

I am writing a new novel and have reached the point where I need an evil object, something quite ordinary looking however it holds or is imbued with enough evil energy/power that if it falls into the wrong hands it has the potential to destroy the world.

Here're a few sketchy details about the book- there is a feud between a 25-year old black wizard and his 23-year old black witch sister that erupts when she sends a demon to murder their father (who has been the guardian of this vast magical treasure trove and this object since his father passed on) and her brother (to whom the guardianship is passed upon the death of the father since it passes to the next male heir in line) so that she, as the last living person in the line assumes guardianship of these items and that particular object. Being a female she has had no access to this hoard, but is aware of it through her family history. She is corrupted, demented and has become a megalomaniac. She wants her brother dead. His options are limited. So, he has hooked up with a young, white witch-druidess who is not quite 21-years old, and gathered a motley crew of similar white magic practitioners from among her family and friends, plus two iffy dark arts practitioners as allies.

He's a potter by trade, working at the family business that has been in existence since the late 1600's, and lives in the ancestral homestead, also of that era. He's already bonded himself to the young white witch to save her from a demon sent to kill him that attacks her-so technically, by his dark arts laws and covenants, he's married to her, which doesn't make her grandfather, mother or anyone else she knows in the white arts any too happy. And he's also created his heir with her which doesn't make anyone happy, and makes it imperative that she survives what lies ahead so the bloodline continues.

To help her understand why it is so important that he defeats his sister when she initiates an all out war against him, he takes the white witch down beneath the earth under the house and shows her what it is he is charged with guarding with his life...

At the very deepest level of this subterranean storehouse of magical items, etc., is a vault that contains this one object- an ordinary looking thing...but it contains concentrated evil energy...and it has the power to destroy the world.

What is the object?

I need some ideas. Four people have offered suggestions so far on facebook. In addition to the object you can also give the object a little back story as to how it came to be. You have until noon next Saturday, June 4th to respond here on my blog, or by sending me an email at sebuffum415@gmail.com, or by posting on either of my facebook pages.

Your reward for helping? Acknowledgement of your contribution on the dedication page of this novel, and one signed copy. In the case of my choosing an object suggested by one person and the back story contributed by another person then both contributors will be acknowledged and given one signed copy apiece when the book is published later this year.

Meanwhile, I'm going to finish the novel this week. I'll plug in a stand-in object and a sketchy back story for now.

Thanks in advance for your invaluable assistance! I enjoy getting readers involved with my books and look forward to seeing the suggestions you come up with.