Question

What is the hardest rock and what is its compressive strength (PSI)?

Asked by: Ed Mendoza

Answer

Diamond, since it is a natural mineral, would be considered a 'rock.' Diamond has a bulk modulus (reciprocal of compressibility) of 443 GigaPascals (GPa). One GigaPascal is equal to 14503.77 PSI. Therefore, the incompressibility of diamond is about 6.425 million PSI or 437,200 Atmospheres.

Diamond was once thought to be the hardest and the most incompressible material on earth, either natural or man-made. Although diamond is still considered the hardest, the bulk modulus of the metal osmium has recently been found to be 476 GPa. That is over 7% more incompressible than diamond, but it is never found pure enough in nature to challenge the diamond.

Answered by: Scott Wilber, President, ComScire - Quantum World Corporation

Search

Loading






Science Quote

'We are all in the gutter, but some of us are looking at the stars.'

Oscar Wilde
(1854-1900)

Top Selling

Here are our physics & astronomy bestsellers:
Magnetic Levitator - Classic
KonusScience 5 Way Microscope Kit
Snap Circuits Jr.
CHEM C2000 Chemistry SuperKit v2.0
Periscope
Space Wonder Gyroscope
Solar Radiometer
Mini Plasma Ball
Smart Robot 4M Kit
130 Electronics Projects Kit

Sponsors

USC University of Southern California Dornsife College Physics and Astronomy Department McMaster University Physics and Astronomy Department