Elements Whose Symbols Seem Illogical

1. Sodium – Na (from the Latin word "natrium")
2. Potassium – K (from the Latin word "kalium")
3. Iron – Fe (from the Latin word "ferrum")
4. Copper – Cu (from the Latin word "cuprum")
5. Silver – Ag (from the Latin word "argentum")
6. Tin – Sn (from the Latin word "stannum")
7. Antimony – Sb (from the Latin word "stibium")
8. Tungsten – W ("wolfram " after the tungsten mineral wolframite)
9. Gold – Au (from the Latin word "aurum")
10. Mercury – Hg (from the Latin word "hydrargyrum")
11. Lead – Pb (from the Latin word "plumbum")

Source: http://www.webelements.com/