low-background lead

Noun

 * 1) Lead with low inherent radiation levels, suitable for instruments and experiments highly sensitive to.
 * 2) Lead sourced from ancient shipwrecks, where the deep sea environment has kept it from accumulating radiation from outside sources, and where inherent radiation has decayed away in the time it has been sunk.
 * 1) Lead sourced from ancient shipwrecks, where the deep sea environment has kept it from accumulating radiation from outside sources, and where inherent radiation has decayed away in the time it has been sunk.