Learning how to mix watercolour greys (or grays - depending how you spell it in your part of the world) causes confusion for many artists.
There's hundreds of potential greys available if you know what colors to mix - and it's not a simple matter of black and white either.
In fact, talking of black and white, those colors make a fairly dull, boring grey with very little character.
Some of the blues and reds or browns mixed together provide a beautiful way of mixing greys, which can be further extended by dominating the mix with one or the other color.
Have a look at the combinations of colors I've used throughout this article to see what I mean.
And don't forget, this is just a tiny example of what you can achieve with different reds, blues and browns.
And I've not even mentioned adding the odd touch of yellow either...
By the way, even though the examples I've used are watercolors, the same principles (and often colors as well) apply whatever medium you're using.
To the left of each color the blue dominates, whilst the red or brown is predominant on the right. In the centre of the mix is approximately 50-50 of each.
Try other reds, blues and browns that I've not shown and see what greys emerge...
As a matter of interest, these colors I've shown are often what people describe as 'mud' when their picture goes wrong. Well, you can see that there's nothing wrong with a 'mud color' if it's used in the right place.
Oh, and don't assume that every red and blue automatically makes purple incidentally.
If the red, especially, has a touch of yellow in it like Cadmium Red or Light Red, it will produce a grey when mixed with, say, French Ultramarine.
This is because then you effectively are mixing three primary colors - Blue, Red - and the touch of Yellow that's in the Red....
You can also add further variety when mixing greys by adding more or less water in the watercolor versions or white in acrylics, oils etc.
To the left of each color the blue dominates, whilst the red or brown is predominant on the right.
In the centre of the mix is approximately 50-50 of each.
Try other reds, blues and browns that I've not shown.
To make things simple for yourself when learning how to mix watercolour greys, just use two blues and two reds/browns to start with.
These will give you several options which can be extended by lightening or strengthening and varying the ratios of color as I suggested.
By the way, if you mix the colors on your paper or canvas as you're applying the paint, rather than just mixing it on the palette, you'll get a very vibrant range of partially mixed greys with real character.
Now you don't normally associate 'grey' with 'vibrant' - but try it and see!
When you get used to these, add another blue or red/brown and see what this brings.
Make a color chart noting all your color combinations and strengths.
Keep this simple - eg: 1 dollop of Cobalt Blue to 3 of Light Red.
It's fun and quick to produce and provides a brilliant reference card for the future...
By all means download the images here on the article, but remember that computer screens and printers all show colors a little differently.
It's much better to start mixing grays from your own paints so you can see exactly what they look like on your paper and canvas.
Best of luck and enjoy...!