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The element with the highest melting point is usually given as carbon, at about 3,823 K (around 3,550 °C). The highest melting point of any metal belongs to tungsten: 3,695 K, or about 3,422 °C. There’s a catch with carbon, though, and it’s worth understanding.
The top 10 (from our element data)
| Rank | Element | Melting point (K) | Melting point (°C) |
|---|---|---|---|
| 1 | Carbon | 3,823 | ~3,550 |
| 2 | Tungsten | 3,695 | ~3,422 |
| 3 | Rhenium | 3,459 | ~3,186 |
| 4 | Osmium | 3,306 | ~3,033 |
| 5 | Tantalum | 3,290 | ~3,017 |
| 6 | Molybdenum | 2,896 | ~2,623 |
| 7 | Niobium | 2,750 | ~2,477 |
| 8 | Iridium | 2,719 | ~2,446 |
| 9 | Ruthenium | ~2,607 | ~2,334 |
| 10 | Hafnium | ~2,506 | ~2,233 |
For comparison, iron melts at about 1,538 °C and the surface of the Sun is roughly 5,500 °C.
The carbon catch
At normal atmospheric pressure, carbon doesn’t melt at all. Graphite sublimes — it turns straight from solid to gas — at around 3,640 °C. Liquid carbon only exists at high pressure (roughly 100 times atmospheric pressure or more), and the melting point quoted in tables refers to those conditions. Measuring it is extraordinarily difficult, which is why published values vary by a few hundred degrees.
So some sources say tungsten has the highest melting point of any element, with carbon disqualified on the technicality. Both answers can be found in reputable references; the key is knowing why.
Why these elements are so hard to melt
Melting a solid means overcoming the forces holding its particles in place.
- Carbon (as graphite or diamond) is a giant covalent network: every atom is joined to its neighbours by strong covalent bonds. To melt it, you’d have to break a vast number of those bonds.
- Tungsten, rhenium, osmium and tantalum are transition metals in the middle of period 6. They have many valence electrons (5d and 6s) contributing to metallic bonding, and heavy, compact atoms. Around the middle of each transition series the d orbitals are about half filled, which gives the strongest metallic bonding — so melting points peak there.
You can see this pattern clearly in the melting point trend map: a hot stripe down the middle of the d-block, peaking at tungsten.
Why it matters
- Light bulb filaments. Incandescent bulbs used tungsten filaments because tungsten can glow white-hot without melting.
- Welding. TIG welding uses non-consumable tungsten electrodes.
- Rocket nozzles and spacecraft. Tantalum, niobium and tungsten alloys handle extreme temperatures.
- Jet engines. Rhenium is added to the nickel superalloys in turbine blades to help them survive near their melting points.
- Furnace linings and crucibles. Molybdenum and tungsten are used for high-temperature furnace parts.
Hottest melting compounds
Some compounds melt even higher than any element. Tantalum hafnium carbide and hafnium carbide are among the most heat-resistant materials known, with melting points around 3,900 °C or more, and recent studies suggest some hafnium–carbon–nitrogen compounds could go higher still.
The lowest melting points
At the other extreme, helium doesn’t solidify at all at normal pressure, no matter how cold it gets — it needs about 25 atmospheres of pressure to freeze near absolute zero. Among metals, mercury melts at −38.8 °C. See the element with the lowest melting point.
Quick answers
What metal has the highest melting point? Tungsten, at about 3,422 °C.
What element has the highest boiling point? Rhenium and tungsten, both around 5,500–5,600 °C in our data. See highest boiling point element.
Is diamond harder to melt than tungsten? At high pressure, yes. At normal pressure it doesn’t melt — it converts to graphite and then sublimes, or burns if oxygen is present.
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