The henna/cassia thread

[Elettaria]

We have a huge thread for cassia, and umpteen threads for henna, but we don't appear to have a thread for those who use henna with cassia. Let's get started! I'm particularly interested in knowing what proportions and recipes produce what colour results on different hair colours, with pictures of course. I'm also curious about whether one herb becomes dominant in a mix. For example, I've heard that the henna colour will easily take over a henna/cassia mix, that a 50:50 blend will produce a colour closer to that produced by henna than someone half-way. Is this definitely true, and what happens with the other features of the herbs? Are the conditioning properties closer to that of henna, or are they in the middle? If you find that henna leaves your hair glorious but cassia leaves it a bit dry, what's a mix likely to do? What about ease of application? How about the staining power on skin of the little bits of henna/cassia which creep out when you're applying the stuff? Do you find there are any differences when mixing up the blend, such as when determining whether dye release has occurred?