I've been waiting for some hot, humid, soggy DC weather before I wrote in. This deodorant is a huge success. Thank you TeresaT and IrishLass for experimenting, and to all the others for trying the original and variations. We had 3 days of very hot weather (from 80s to mid-90s, and it worked beautifully. Every night at 10 or so, I do a sniff test and am sort of amazed that there's nothing but EO scent. My formulation was for a total of 100 grams, and that filled a 3.5 oz. deodorant tube (from Amazon) with enough left over for a little jar. I used (by weight) 57 grams of Babassu oil, 40 grams of magnesium hydroxide and 3 grams of beeswax. Melted in a glass jar, in hot water, stirred well, and added several drops of rosemary and lavender EOs. When it cooled slightly, I poured it into my deodorant tube, and had a bit left that I kept in a small jar. (My notes show that 40 grams of magnesium hydroxide equalled approx. 1/2 cup, if that helps anyone!)
The deodorant is holding its shape, not melting at all, and glides well. I keep it in my bathroom and I have the air-conditioning at about 78-80 degrees. I can also put it on right after shaving with no stinging. I also wear mostly dark tops and haven't noticed any white film or marks. I LOVE THIS STUFF. Thank you so much for this crazy, fun thread and all the help.
Mary