The outermost shell of each carbon atom has four electrons. In diamond, these electrons are shared with four other carbon atoms to form very strong chemical bonds resulting in an extremely rigid tetrahedral crystal. It is this simple, tightly-bonded arrangement that makes diamond one of the hardest substances on Earth.

Such a collision would create perturbations in the fabric of spacetime which would leave an imprint on the cosmic microwave background radiation. The background radiation is the universe’s first light, made up of photons that were released throughout the universe a mere 370,000 years after the big bang.

While diamonds may be the hardest naturally occurring substance found on earth, he explains, they are not the hardest available (there are two harder substances – a laboratory synthetic nanomaterial called wurtzite boron nitride and a substance found in meteorites called lonsdaleite).

Talc is the softest mineral on Earth. The Mohs scale of hardness uses talc as its starting-point, with a value of 1.

Gold is clearly the most durable, but many objects fashioned from silver, copper, bronze, iron, lead, and tin have survived for several thousand years.

Tungsten

Strongest Metals for Wedding Bands

• Tungsten.
• Ceramic.
• Titanium.
• Platinum.
• Palladium.
• Stainless Steel.
• Cobalt.

Six of the Most Conductive Metal Coatings Available

• Silver: The single most conductive metal, silver conducts heat and electricity efficiently thanks to its unique crystal structure and single valence electron.
• Copper: Like silver, copper’s single valence electron makes it a highly conductive metal.

Variable electrical conductivity – diamond does not conduct electricity, whereas graphite contains free electrons so it does conduct electricity. Silicon is a semi-conductor – it is midway between non-conductive and conductive.

Brass is only 28% as conductive as copper. Some bronzes are as low as 7% as conductive as copper! Copper is the standard by which electrical materials are rated and conductivity ratings are expressed as a relative measurement to copper….Electrical Conductivity of Materials.