Nephrite is one of the varieties of jade; it is more opaque and cheaper than jadeite. It can be found in eggshell white, black, brown, golden, and various shade of green, including forest green; the last is the most valuable. It is more commonly used for carvings but can also be found in jewelry -- in cabochons, beads, or as the background for cameo jewelry. And just because something is nephrite rather than jadeite doesn't mean it's any less "real jade" -- some beautiful things can be made from nephrite.