Boron, arsenic, and antimony, among other substances, are used as dopants when added to a pure semiconductor material to alter its electrical characteristics.
Artificially produced gemstones[?] (such as Ruby (gemstone)) usually contain a dopant to identify them as such.
... Interview (an interview conducted ten years since Barsamian first interviewed Chomsky)
Rollback: The Return of Predatory Capitalism
History and Memory
Th ...