A recent enquiry from New Zealand prompted me to spend a very enjoyable afternoon in my studio making a colour wheel from the full range of Michael Harding paints! I placed each tube in spectrum order around the wheel with 'duplicate' hues placed around the outside of the wheel, aligned directly behind a colour if they were of the same hue, though made from different pigments, or perhaps with different tonal value or saturation level.
I have received enquiries about where the earth pigments would belong on this wheel. Basically, they mostly fit between the bright yellows and the purple reds. Some earths are low saturation yellows (Ochres for example), browns are low saturation oranges (Burnt Sienna or Burnt Umber) and red-browns are low saturation reds (Transparent Oxide Red, Indian red), Raw Umber has a green-ish note to it but most of the others fit between the yellows and the reds. Here are some close-up images for those of you who might like to read all the labels - I hope they are sharp enough for you to see!
Here's a link to the Michael Harding website in where you can find loads of fascinating information about each colour https://www.michaelharding.co.uk/