On the cheap end, I've used Nigari (magnesium chloride the Japanese use for coagulating tofu). I order from here <[
www.naturalimport.com] I've got a 20 kg (44 pound) bag in my garage. I had it tested for heavy metals by a local lab a number of years ago. Very clean. The results are posted here in the archives. For topical use, to make "magnesium oil" you just add enough water to dissolve the mag. It feels oily, but there is no oil. Very effective and very inexpensive per gram of magnesium.
You can also do the same thing with epsom salt from the drugstore.
For either, just apply & let dry. You can wash off or let stay after it has dried.
George
