"Madder, Woad, and other ancient dyes" Topic

My goal is to create a historically accurate, vibrant and diverse representation of the Polybian era Roman legion that captures that citizen milita look while still being able to tell from a distance what kind of unit it is.

My planned layout is as follows:

Velites – natural wool colors only (off white, beige, brown)
Hastati – off white and washed out/pastels of madder red, blues, woad, pale yellows and greens
Principes – more vibrant versions of the above (more wealth = can afford more dye) with minor edging of contrasting colors
Triarii and officers – brighter white, reds from bugs, non-Tyrian purples with occasional edging
Equites – similar to the above, but with tyrian/wine red clavi lines
Consul and bodyguards – same as above with tyrian purple cloak

So here's the problem: looking at my paints (primarily Vallejo Model with some Army Painter), I noticed I didn't have anything that looked like madder, woad, or pastels poorer soldiers would wear. Oh well, I think, I'll just look online and buy a few paints. However, looking at various paint suppliers, I don't see anything that looks like real life madder etc. When painting a washed out color, what techniques do you all use?

Thin the paint

I added progressively greater amounts of off white to indigo to represent clothing that was fading.

Grelber

I often try to paint in subdued, washed out colors for alot of my armies. They are colorful but muted.

I typically look for duller colors as my base. Medium blue-grey's, dark reds, yellow greens, grey whites, etc. From there I use off-white added to the base color to create my highlights. Here are some pictures of a Thirty Years War army that I painted up with this palette approach:
link

There is no one correct colour for madder. Have a look at this website (scroll to the bottom of the page for some good dye colour samples, I think quite few Vallejo colours would be useful. Also note the colours produced by rtying to eke more out of the vat – the colour goes from quite a strong red to a pale orange. That could be helpful when thinking about the class of soldier:

link

Cheers,
John

This video may be of value. It shows the common colours of the period in question and where it comes from.
YouTube link

This video may also be of interest. Its not as good as the previous video but it does outline the effect of age on colours.
YouTube link

Inks and washes can be effective. The Citadel contrast paint and similar can give a good effect.

Wargames Foundry do a nice Madder triad.

Thank you for the resources, everyone!

On further research, I don't think I'll be using pure yellow. Apparently it, alongside orange, was considered a more feminine color associated with bridal gowns.