Skip to content

Free US shipping30-day returns

The Tungsten Cube

Comparison

Tungsten vs osmium

Osmium wins on the only metric tungsten cubes are bought for. At 22.59 grams per cubic centimetre it is the densest naturally occurring element, about 17% denser than tungsten.

It is also the reason the phrase 'the densest metal you can reasonably own' has a qualifier in it.

19.3
Tungsten g/cm³
22.59
Osmium g/cm³
1.17×
Osmium is denser

Cube weight, tungsten vs osmium

Cube sizeTungstenOsmiumDifference
1″316 g370 g−54 g
1.5″1.07 kg1.25 kg−182 g
2″2.53 kg2.96 kg−431 g
3″8.54 kg9.99 kg−1.46 kg

Why nobody sells osmium cubes

Osmium is roughly a thousand times rarer than tungsten in the earth's crust, and it is recovered almost entirely as a byproduct of platinum and nickel refining. Annual global production is measured in the low hundreds of kilograms.

It is also brittle rather than tough, difficult to work, and priced accordingly. A 1.5-inch osmium cube would weigh 1.25 kg and cost more than most cars.

The toxicity problem

Osmium metal slowly oxidises in air to osmium tetroxide, which is volatile, genuinely toxic, and damaging to eyes and lungs at low concentrations. It is handled in laboratories with real precautions.

Crystalline osmium is sold as a collectible and is treated as stable in that form, but it is not a thing anyone recommends passing around a room.

Iridium, the near-tie

Iridium is 22.56 g/cm³, within measurement error of osmium, and the two swap places depending on whose figures you read and how the density was determined. Both are far outside the range of a desk object.

For anything you actually intend to hold, tungsten is where the curve stops.

Common questions

What is the densest metal?

Osmium at 22.59 g/cm³, with iridium essentially tied at 22.56. The two are close enough that measurement method decides the ordering.

Is osmium denser than tungsten?

Yes, by about 17%. Osmium is 22.59 g/cm³ and tungsten is 19.3. A 1.5-inch osmium cube would weigh 1.25 kg against tungsten's 1.07 kg.

Why not buy an osmium cube instead?

Rarity, cost and toxicity. Osmium is around a thousand times rarer than tungsten, costs orders of magnitude more, is brittle, and oxidises to toxic osmium tetroxide. Tungsten is the densest metal that is practical to handle.