Koh-i-Noor
From Tardis Wiki, the free Doctor Who reference
The Koh-i-Noor was a diamond owned by Queen Victoria, among others. There was a myth that whoever owned the diamond must surely die. Albert, the Queen's husband, constantly had it cut in order for it to exist to the exact specifications he needed for it to work with the light chamber.
In 1879, while being taken to a jeweller to have the stone recut, it was used in combination with the light chamber to kill a Lupine Wavelength Haemovariform. (DW: Tooth and Claw)