the.com/hardness
the measure of how much a material refuses to be scratched, dented, or talked into compromise
means the quality or degree to which a material resists scratching, denting, or deformation, or more broadly the state of being firm, unyielding, or harsh.
from From Old English 'heardnes,' built from 'heard' (hard, firm, severe) plus the noun-forming suffix '-nes.' The root 'heard' traces back to Proto-Germanic '*harduz' — a cousin of German 'hart' and Dutch 'hard' — and likely further still to a Proto-Indo-European root meaning 'strong, bold,' which also seeded the Greek 'kratos' (strength, power), the same force lurking in words like 'democracy.' So the unscratchable diamond and the autocrat share a distant ancestor in sheer toughness.
- diamond king
- Tops the Mohs scale at a flawless 10
- scratch test
- Mohs ranks minerals by which scratches which
- water cred
- Hard water is just dissolved calcium and magnesium
- steel proof
- Rockwell hardness presses diamonds into metal to score it
- diamond vs diamond
- Only a diamond can scratch another diamond
mohs hardness scale — friedrich mohs ranked 10 minerals by hardness in 1812, with diamond at 10
vickers hardness test — uses a diamond indenter to measure material hardness on metals and ceramics
brinell hardness test — applies a steel or tungsten ball under load to measure hardness of metals since 1900