Marc Delafontaine
Encyclopedia
Marc Delafontaine was a Swiss
chemist
who in 1878, along with Jacques-Louis Soret
, first observed holmium
spectroscopically. In 1879, Per Teodor Cleve
chemically separated it from thulium
and erbium
. The three are given credit for the element's discovery.
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
chemist
Chemist
A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms...
who in 1878, along with Jacques-Louis Soret
Jacques-Louis Soret
Jacques-Louis Soret was a Swiss chemist who in 1878, along with Marc Delafontaine, first observed holmium spectroscopically. Independently, Per Teodor Cleve separated it chemically from thulium and erbium in 1879...
, first observed holmium
Holmium
Holmium is a chemical element with the symbol Ho and atomic number 67. Part of the lanthanide series, holmium is a rare earth element. Its oxide was first isolated from rare earth ores in 1878 and the element was named after the city of Stockholm....
spectroscopically. In 1879, Per Teodor Cleve
Per Teodor Cleve
Per Teodor Cleve was a Swedish chemist and geologist.After graduating from the Stockholm Gymnasium in 1858, Cleve matriculated at Uppsala University in May 1858, where he received his PhD in 1863...
chemically separated it from thulium
Thulium
Thulium is a chemical element that has the symbol Tm and atomic number 69. Thulium is the second least abundant of the lanthanides . It is an easily workable metal with a bright silvery-gray luster...
and erbium
Erbium
Erbium is a chemical element in the lanthanide series, with the symbol Er and atomic number 68. A silvery-white solid metal when artificially isolated, natural erbium is always found in chemical combination with other elements on Earth...
. The three are given credit for the element's discovery.