<human>:  Can a diamond float on water?
<bot>: No, a diamond is an Allotrope of carbon that is too dense to float on water. Diamonds are formed by extreme heat and pressure being applied to carbon under the earth's crust. The density of a diamond is 3.51 g/cm3. The density of water is 997 kg/m3. A diamond is more dense than water. A diamond will sink in water. So, no.