[topher515]

You’re suggesting that a cubic meter of stone weighs just 3 kg (6.6 lbs)?

That doesn’t sound right.

[athenot]

2.7 Kg/dm³

(Just noticed that Unicode U+3379 is the DM CUBED glyph but doesn't render on the mac, unlike ㎣, ㎤, ㎦)

[krick]

He obviously meant 3 000 kg. Easy to make a mistake, since 3 kg would be 1 liter, which is more common way to think about densities.