Short answers, pulled from the story.
William Hyde Wollaston discovered palladium on the 2nd of July 1802 in a London laboratory. He found the new noble metal within crude platinum ore sourced from South America but did not announce his finding immediately.
Palladium possesses a unique ability to absorb hydrogen that defies the behavior of other metals by acting as a sponge that can hold up to nine hundred times its own volume of the gas. This property allows hydrogen to diffuse rapidly through heated palladium, creating a membrane that is essential for producing high-purity hydrogen in laboratory settings.
Richard F. Heck, Ei-ichi Negishi, and Akira Suzuki won the Nobel Prize in Chemistry in 2010 for their work on palladium-catalyzed cross couplings. These reactions allow scientists to join carbon atoms together with unprecedented precision, forming the complex molecular structures required for modern medicine and materials science.
More than half of the global supply of palladium is consumed by catalytic converters, devices that transform as much as 90% of the harmful gases in automobile exhaust into nontoxic substances. These converters contain palladium, rhodium, and platinum to convert hydrocarbons, carbon monoxide, and nitrogen dioxide into nitrogen, carbon dioxide, and water vapor.
Hallmarking became mandatory in the United Kingdom in 2010 for all jewelry advertising pure or alloyed palladium. Palladium has been used as a precious metal in jewelry since 1939, serving as a natural alternative to platinum in alloys known as white gold.
Russia's Norilsk Nickel ranks as the largest producer globally, accounting for thirty-nine percent of the world's production. The most extensive sources of palladium ore are found in the norite belt of the Bushveld Igneous Complex in South Africa, the Stillwater Complex in Montana, and the Sudbury Basin in Ontario.