different between blackness vs murkiness

English

From Middle English blaknesse, equivalent to black +? -ness.

blackness (usually uncountable, plural blacknesses)

The state or quality of being black.
The blackness of outer space comes from the lack of anything to reflect light rather than the absence of light.
The state of being of African descent.
- 2018, David Betancourt, ‘Black Panther’ fully embraces its blackness -- and that's what makes it unforgettable, The Washington Post:
  “Black Panther” is a stunning visual and cultural achievement that takes superhero cinema where it’s never gone before by not being afraid to embrace its blackness.

From Middle English mirkines, equivalent to murky +? -ness. Compare also Middle English mirkenes, merkenes (“darkness”).

murkiness (usually uncountable, plural murkinesses)

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