Finnish chemist best known for identifying the new earth yttria. During this period the term "earth" referred to any oxide resistant to heat and insoluble in water. Yttria was later shown to contain several new elements now called rare-earth elements. In 1886 Jean Marignac named the new rare-earth he had discovered gadolinium, the first element named after a person. Gadolin was active in politics and played an active role in Finland's secession from Sweden.