Galena diode. Making such wireless receivers was a popular home hobby in Britain and other European countries during the 1930s. Scientists associated with the investigation of the diode effect are Karl Ferdinand Braun and Jagadish Bose. In modern wireless communication systems, galena detectors have been replaced by more reliable semiconductor devices. Galena Galena, also called lead glance, is the natural mineral form of lead(II) sulfide. It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic crystal system often showing octahedral
Minette (ore) low iron content, however, meant that Lotharingian Minette-ore was successively replaced by more highly concentrated imported ores (with iron contents around 60%). As a consequence, more and more mins were closed down. The last pit in Luxembourg, Differdange, closed in 1981, the last French one, at Audun-le-Tiche in the Moselle department did so in 1997. Minette (ore) Minette is a type of mineral deposit, consisting of iron ore of sedimentary origin, found in the south of Luxembourg and in Lorraine. Minette ore was deposited in the Early Jurassic and Middle Jurassic. The term "Minette" came from French miners. It is