I know this is a wicked old post, but incase anyone else stumbles upon it, I use rare earth in my soil & love it. I did a small outdoors last summer, gave a few to a friend to finish inside, and am doing my 1st indoors now. Think its a great organic source of silica for your plants & contains 60% pyrophyllitic silicate clay + 40% leonardite, which is full of humates, fulvates & other trace elements. . I believe its responsible for the amazingly strong and thick stems and braches my lil girls already have, and teh ones last years did as well.
I was thinking of using both rare earth & diamond black, which is 100% leonardite clay (100% humates & fulvates) but dont know if i can make it to the store before i transplant. Leonardite clay is what most, if not all ,humic acid products are made from. AN's grandma enggys stuff is all made from different aspects of this mineral.
Ok, again I realize this post is over a year old but I came across it and some one else may as well. Always try to spread the knowledge
P&L