Chemistry: A Volatile History to investigate. Marie Curie began her investigations by testing a uranium ore called pitchblende with an electrometer. She discovered it was four times more radioactive than pure uranium, and wondered if this was due to the presence of an even more radioactive element in the pitchblende. Curie began stockpiling tonnes of pitchblende, then in the most basic of workshops with primitive equipment she undertook a multitude of complex and dangerous procedures in an attempt to isolate this new element. In the event, Curie discovered two new elements, polonium named after her native Poland and radium. Whilst these were naturally occurring
Period 5 element ("Em"). In 1937 technetium (specifically the technetium-97 isotope) became the first predominantly artificial element to be produced, hence its name (from the Greek , meaning "artificial"). Its short-lived gamma ray-emitting nuclear isomer—technetium-99m—is used in nuclear medicine for a wide variety of diagnostic tests. Technetium-99 is used as a gamma ray-free source of beta particles. Long-lived technetium isotopes produced commercially are by-products of fission of uranium-235 in nuclear reactors and are extracted from nuclear fuel rods. Because no isotope of technetium has a half-life longer than 4.2 million years (technetium-98), its detection in red giants in 1952, which are billions of