10. Tantalum


Chemical element with the symbol Ta and atomic number 73.

Tantalum grafika

  • density: 16,650 kg/m³
  • discovery: Ekeberg (1802)
  • atomic mass: 180,947 u
  • Mohs hardness: 6.5

9. Uranium


The chemical element with the symbol U and atomic number 92.

Uranium grafika

  • density: 19,050 kg/m³
  • discovery: Klaproth (1789)
  • atomic mass: 238,028 u
  • Mohs hardness: 4.5

8. Tungsten


Chemical element with the symbol W and atomic number 74.

Tungsten grafika

fot. Cccucumber / wikipedia.org (CC BY-SA 4.0)

  • density: 19,250 kg/m³
  • discovery: Brothers de Elhuyar (1783)
  • atomic mass: 183,84 u
  • Mohs hardness: 7.5

7. Gold


The chemical element with the symbol Au and atomic number 79.

Gold grafika

  • density: 19,300 kg/m³
  • discovery: prehistory
  • atomic mass: 196,966 u
  • Mohs hardness: 2.5

6. Plutonium


A radioactive chemical element with the symbol Pu and atomic number 94.

Plutonium grafika

  • density: 19,816 kg/m³
  • discovery: Glenn Theodore Seaborg (1941)
  • atomic mass: 244,0642 u
  • Mohs hardness: ???

5. Neptunium


Chemical element from the actinide group, atomic number 93.

Neptunium grafika

  • density: 20,200 kg/m³
  • discovery: McMillan and Abelson (1940)
  • atomic mass: 237,0482 u
  • Mohs hardness: ???

4. Rhenium


The chemical element with the symbol Re and atomic number 75.

Rhenium grafika

  • density: 21,020 kg/m³
  • discovery: Walter Noddack, Ida Tacke, and Otto Berg (1925)
  • atomic mass: 186,207 u
  • Mohs hardness: 7

3. Platinum


The chemical element with the symbol Pt and atomic number 78.

Platinum grafika

fot. Periodictableru / wikipedia.org (CC BY-SA 3.0)

  • density: 21,090 kg/m³
  • discovery: Scaliger (1557)
  • atomic mass: 195,084 u
  • Mohs hardness: 3.5

2. Iridium


The chemical element with the symbol Ir and atomic number 77.

Iridium grafika

  • density: 22,420 kg/m³
  • discovery: Smithson Tennant (1803)
  • atomic mass: 192,217 u
  • Mohs hardness: 6.5

1. Osmium


A chemical element from the ferrous metal group with the symbol Os and atomic number 76.

Osmium grafika

fot. Periodictableru / wikipedia.org (CC BY-SA 3.0)

  • density: 22,590 kg/m³
  • discovery: Smithson Tennant and William Hyde Wollaston (1803)
  • atomic mass: 190,23 u
  • Mohs hardness: 7