How to make "Coal Black" paint mixture?

I had to make some Anthracite gray once for a boat and I just used black, a "touch" of grey and like one drop of dk blue...  I had no color refs to go on but by the description in several refs it sounded about right to me...

I don't know if this will help, but here are 2 different (possible) solutions...

1 - Homemade Charcoal
I've had to mix a charcoal to match a ColourCoats shade (see: http://www.rocketcopy.biz/models/rokket/uboat/paint.shtml - paint chart at bottom "Dark Charcoal")

Humbrol "Black Green" #91 - 1 part
Humbrol "RAF Blue"  #91 - 2 parts
Humbrol "Black"  #33 - 1 part

It's a lovely charcoal that looks very black, but really dark-dark gray, but not just gray, it has a "life" to it (from the blue), but doesn't look blue. I tried 20 tests to match this charcoal I was after, and so many came out black or gray. You could mess around with other colors too


2 - Graphite
This is another great gray-black, funky and also good for simulating cast iron. get Graphite Powder (easy - automotive/mechanical lubricant in K-Mart, dept store auto sections, hardware stores).  It's extreeeeeeeeemly fine and slippery. (A substitute is to buy an stick of graphite, an artist's pencil, and shave it into bits...not as handy but still works.)

I mixed the powder with a bit of flat black paint. For literal cast iron, a rough surface, get it clumpy. For fine, less. BRUSH on (I would be game to put thru an airbrush.) When dry, it looks like a thick flat black and nothing special. But then you LIGHTLY sand it: this crushes the powder trapped in the paint and makes a nice weird very charcoal effect. Fine sanding film is good, as are the foam/cloth modern ladies' nails emery boards, but they get stained black very quickly.

The final effect is like a less-sparkly gunmetal color.

CAUTIONS for graphite:
1 -  too much sanding will go through to base; 2 - it is also difficult to get a uniform finish over a large area; 3 - this stuff is FINE and will turn anything it touches black, and is probably harmful to breathe, use a paper paint mask.

Good luck!

One person's black is another person's dark gray.

Seriously, paint shading (that's what it's called in the industry) is an intimate mix of art and science—and it gets totally arcane when all you have is a color name! or two! One says gray, another says black.

In fact, anthracite coal is as close as nature comes to a true black of resinous luster. The closest flat black is "lamp black"—soot from a kerosene lamp.

Bituminous coal (the most common kind) is generally blue-black with occasional redish tints.

I know whereof I speak—I'm a retired professional geologist, and I have perfect color vision (It's required in my former line of work.) and before that, I made a living helping people shade paint to quality control standards.

An FS number or RLM would help. A near CYMK swatch would help—heck, RGB would be better than nothing.