On how to colour and tint foundations and bases I found this entry: http://mychemicalpeel.blogspot.ca/2012/04/boost-healing-and-protection-a...
I’ve found a remedy that actually adds even more healing and protective power to my skin, before and after chemical peels. Using my mortar and pestle, I grind just a pinch of Turmeric (also called curcumin; species is C. Longa or Curcuma Longa) with the zinc, and this gives it a light beige color (can be adjusted to vary the color).
My skin's undertone is slightly yellow, so turmeric works really well to achieve a natural color for me, but if I had an olive or darker undertone, 100% cocao powder would be perfect as a replacement for turmeric. Cocao powder (100%, as in the product linked) provides an incredible array of benefits for the skin! I also use this cocao powder in my smoothies!
Turmeric benefits the skin too, so just like my uncoated zinc oxide, it acts as an antibacterial agent. In addition, it has been shown to have UV photoprotective properties (which is boosting the SPF even more) and the ability to help wounds heal better. Turmeric is also a very strong antioxidant, so it will neutralize free radicals on the skin, which will protect against further damage. Turmeric has numerous benefits; I could devote an entire post to it, so any time I can incorporate it with my routine, I will.