Usma, a leafy green herb, is sold in all Tajik markets. You can get a small bunch for about $0.06. The process is simple but effective, several market women assured me. Take a bunch of usma and let it dry in the sun for a couple hours. Then grind up the leaves until a dark green goo seeps out. Dip a branch of usma-- or a matchstick, if you want to be more precise -- into the goo and smear it on your eyebrows, making sure, of course, to color the space in between. Leave on for 15 minutes, and repeat the smearing process one or two more times. The result is a deep black unibrow, rich and expressive.