This is a storage container, known as a pig, intended for safely holding highly radioactive isotopes used in the medical field for treatment and diagnosis. With the lid on, there is a minimum of one inch of solid lead in all directions between the contents and the outside world. Pigs come in a range of thicknesses and materials, depending on the type and intensity of radiation coming from the object you want to store. Some have just a fraction of an inch of lead, others have more than an inch of depleted uranium (which is a significantly better shielding material than lead, despite being somewhat radioactive itself).
The person I got this pig from has many more like it, as well as other kinds of lead and tungsten shielding products. He doesn't want to be identified publicly, but contact me if you'd like to buy similar objects from him and I can put you in contact. Click the Source link below to see other kinds of things he has available.
Contributor: Theodore Gray
Acquired: 19 June, 2007
Text Updated: 8 December, 2007
Sample Group: Medical