Pitch is a commonly used adjective to describe black and is used both hyphenated and non-hyphenated to describe blacker than normal black. Pitch is a black substance derived from coal or distilling coal tar or wood tar. Its blackness is used to describe extreme or complete blackness. Normally a waterproofing, pitch can also be used to seal tiny gaps where light gets through, necessary for photographic dark rooms.
Dark black suggests that there is a less dark black to compare it with. Dark is not a particularly accurate adjective for the word black, although technically it is attempting to describe extreme blackness, as opposed to a lighter black that would not actually be black. Dark is not a commonly used adjective to describe black.
When black is described as lightless black, lightless accentuates the blackness of black where not even a slight inkling of light is present. The use of lightless as an adjective goes back to before the 12th century and denotes the complete lack of visible light particles. Scientifically, lightless is used to describe blackness that contains no light particles to stimulate the light sensitive rods of the eye. Lightless is an accurate and precise adjective for describing complete blackness.
Ebony black describes a deep lustrous blackness often used for naming dye and paint hues. In hairdressing, ebony black is a natural pure black color as opposed to a blue black or a gray black. Ebony is the blackest and densest of all woods and is a good adjective for describing dense blackness of hair color and solid black objects.
Murky black describes a partial blackness that is usually used to describe a color or the color and consistency of dirty water. A murky black suggests changes in density of the blackness. The adjective murky actually lessens the quality of the blackness it describes. It denotes the same sort of darkness that prevents an observer from seeing the bottom of a pond, puddle or lake.