Kig's Manassa is a good possibility. It's one of my favorite turquoises. I used to buy quite a bit of jewelry set with it from various members of the King family.

There are several other mines that have similar to what I see in the picture. Over the years many mines have produced a variety of colors, not just the typical stone.

I've had blue gem and even turquoise mountain stone in the green with yellow-brown matrix. The matrix in your beads is a little browner or darker brown than typical Kimg's Manassa. If these beards are old and well worn the green color may have originally been blue!

Sun West has good pictures of various stone examples. Their example picture of blue gem includes some green stone: http://www.silversunalbuquerque.com/m-blue_gem.htm
Sky Stone trading used to have good pictures but I don't find them today: http://www.skystonetrading.com/turquoise-mines-and-map/pos/v/chapter/1