Rare Earth Elements

Name: Dysprosium
Symbol: Dy
Atomic Weight: 162.50
Atomic Number: 66
Element Classification: Rare Earth Elements
Discovered By: Paul-Emile Lecoq de Boisbaudran
Discovery Date: 1886 (France)
Name Origin:Greek: dysprositos (hard to get at).
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Symbol: Dy Dysprosium
Atomic Number: 66
Atomic Weight: 162.50
Name: Holmium
Symbol: Ho
Atomic Weight: 164.93032
Atomic Number: 67
Element Classification: Rare Earth Elements
Discovered By: J.L. Soret
Discovery Date: 1878 (Switzerland)
Name Origin:Holmia, the Latinized name for Stockholm, Sweden.
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Symbol: Ho Holmium
Atomic Number: 67
Atomic Weight: 164.93032
Name: Erbium
Symbol: Er
Atomic Weight: 167.26
Atomic Number: 68
Element Classification: Rare Earth Elements
Discovered By: Carl Mosander
Discovery Date: 1843 (Sweden)
Name Origin:Named after the Swedish town, Ytterby.
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Symbol: Er Erbium
Atomic Number: 68
Atomic Weight: 167.26
Name: Thulium
Symbol: Tm
Atomic Weight: 168.93421
Atomic Number: 69
Element Classification: Rare Earth Elements
Discovered By: Per Theodor Cleve
Discovery Date: 1879 (Sweden)
Name Origin:Thule, ancient name of Scandinavia.
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Symbol: Tm Thulium
Atomic Number: 69
Atomic Weight: 168.93421
Name: Ytterbium
Symbol: Yb
Atomic Weight: 173.04
Atomic Number: 70
Element Classification: Rare Earth Elements
Discovered By: Jean de Marignac
Discovery Date: 1878 (Switzerland)
Name Origin:Named for the Swedish village of Ytterby.
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Symbol: Yb Ytterbium
Atomic Number: 70
Atomic Weight: 173.04
Name: Lutetium
Symbol: Lu
Atomic Weight: 174.967
Atomic Number: 71
Element Classification: Rare Earth Elements
Discovered By: Georges Urbain
Discovery Date: 1907 (France)
Name Origin:Named for the ancient name of Paris, Lutecia.
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Symbol: Lu Lutetium
Atomic Number: 71
Atomic Weight: 174.967
Name: Lanthanum
Symbol: La
Atomic Weight: 138.9055
Atomic Number: 57
Element Classification: Rare Earth Elements
Discovered By: Carl Mosander
Discovery Date: 1839 (Sweden)
Name Origin:Greek: lanthanein (to be hidden).
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Symbol: La Lanthanum
Atomic Number: 57
Atomic Weight: 138.9055
Name: Cerium
Symbol: Ce
Atomic Weight: 140.115
Atomic Number: 58
Element Classification: Rare Earth Elements
Discovered By: W. von Hisinger, J. Berzelius, M. Klaproth
Discovery Date: 1803 (Sweden/Germany)
Name Origin:Named after the asteroid, Ceres, discovered two years before the element.
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Symbol: Ce Cerium
Atomic Number: 58
Atomic Weight: 140.115
Name: Praseodymium
Symbol: Pr
Atomic Weight: 140.90765
Atomic Number: 59
Element Classification: Rare Earth Elements
Discovered By: C.F. Aver von Welsbach
Discovery Date: 1885 (Austria)
Name Origin:Greek: prasios and didymos (green twin), from its green salts.
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Symbol: Pr Praseodymium
Atomic Number: 59
Atomic Weight: 140.90765
Name: Neodymium
Symbol: Nd
Atomic Weight: 144.24
Atomic Number: 60
Element Classification: Rare Earth Elements
Discovered By: C.F. Aver von Welsbach
Discovery Date: 1925 (Austria)
Name Origin:Greek: neos and didymos (new twin).
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Symbol: Nd Neodymium
Atomic Number: 60
Atomic Weight: 144.24
Name: Promethium
Symbol: Pm
Atomic Weight: 144.9127
Atomic Number: 61
Element Classification: Rare Earth Elements
Discovered By: J.A. Marinsky, L.E. Glendenin, C.D. Coryell
Discovery Date: 1945 (United States)
Name Origin:Named for the Greek god, Prometheus.
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Symbol: Pm Promethium
Atomic Number: 61
Atomic Weight: 144.9127
Name: Samarium
Symbol: Sm
Atomic Weight: 150.36
Atomic Number: 62
Element Classification: Rare Earth Elements
Discovered By: Jean Charles Galissard de Marignac
Discovery Date: 1853 (France)
Name Origin:Named after the mineral samarskite.
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Symbol: Sm Samarium
Atomic Number: 62
Atomic Weight: 150.36
Name: Europium
Symbol: Eu
Atomic Weight: 151.965
Atomic Number: 63
Element Classification: Rare Earth Elements
Discovered By: Eugene-Antole Demarcay
Discovery Date: 1901 (France)
Name Origin:Named for the continent of Europe.
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Symbol: Eu Europium
Atomic Number: 63
Atomic Weight: 151.965
Name: Gadolinium
Symbol: Gd
Atomic Weight: 157.25
Atomic Number: 64
Element Classification: Rare Earth Elements
Discovered By: Jean de Marignac
Discovery Date: 1880 (Switzerland)
Name Origin:Named after the mineral gadolinite.
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Symbol: Gd Gadolinium
Atomic Number: 64
Atomic Weight: 157.25
Name: Terbium
Symbol: Tb
Atomic Weight: 158.92534
Atomic Number: 65
Element Classification: Rare Earth Elements
Discovered By: Carl Mosander
Discovery Date: 1843 (Sweden)
Name Origin:Named after Ytterby, a village in Sweden.
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Symbol: Tb Terbium
Atomic Number: 65
Atomic Weight: 158.92534