True, they used them because its easier to trade coins than products
It depends on your definition of “ancient.” Radiometric dating using Carbon-14 can reliably date back to about 50,000 years, uranium-lead or lead-lead dating can date back multiple millions, potassium-argon dating can reach 1.5 billion, and rubidium-strontium can reach 50 billion (nearly 4x the age of the universe). It depends on the context in which this question is being asked.
Tungsten has the highest tensile strength of any natural metal, but it's brittle and tends to shatter on impact.
Titanium has a tensile strength of 63,000 PSI. ...
Chromium, on the Mohs scale for hardness, is the hardest metal around.
2,062,305 2,062,305 <span>2,062,305</span>
A sound wave traveling eastward through air<span> causes the air molecules to Vibrate east and west. </span>