Check out these lovely Old Masterly earth pigments from French and Italian ochre mines (except for the Ultramarine, of course... couldn't resist). It's quite moving to think that this has been humanity's palette for most of our history, from cave paintings to Rembrandt's self-portraits.
I ordered them from a company in France as part of my research for the art forgers novel. The pigments were cheap - a euro or so each - but postage was very expensive (flat fee), so it made sense to order lots. Looking at them, I wish I'd ordered even more.
I'm now trying to decide between linseed oil and walnut oil. Might mix two different batches for comparison's sake. What is striking is that all the earth colours harmonise, even the riskier combinations eg the warm, greyish-brownish Terre Verte and the more acidy Terre de Nicoise (the two pots on the bottom left). This could potentially be a disgusting-looking combination reminiscent of an old sofa left out in the rain on a toxic waste site. But it actually turns out to be rather soothing and subtly elegant.