Unraveling

The Unraveling is a powerful magical object.

Description
It is a square of grey cloth containing powerful magic. The magic will unmake any enchantment or transformation it is applied to. It is used by touching the cloth to the relevant object and unravel the threads.

In the series
In Summer Knight, Harry Dresden is given the Unraveling by Mother Winter. It was apparently knitted by Mother Winter herself from grey undyed wool.

Summer Lady Aurora takes the Unraveling from Dresden and later applies it to the statue of Lily, which, after a flash of white light, turns her from stone back to living flesh.