I have been wearing my carnelian 10 motif with the large yg frivoles. This week I went to the boutique and tried on the carnelian earrings. The SA turned to me and said that MUST be my next purchase. I would absolutely wear the earrings together with the 10 (or 20, if I had that). It's certainly good to mix and match, but it's also good to wear a set. I have seen blondes wear sets in yg/mop and ladies with black hair wear onyx sets and I just looooooove that look, where the set compliments the hair color.
BBC, my hair is dark and I am more olive in complexion and I have stayed away from any dark stone around my face, including the much loved Malachite.
I think when next I am in a boutique, I will try the Onyx and see how it looks.