|Prase is a leek green variety of quartz that contains the mineral chlorite. It looks a little like some varieties of amazonite but tends to be harder and more translucent. It is of little interest in the jewelry world.
Chrysoprase is a green chalcedony that gets its color from small amounts of nickel. It can be translucent to opaque with the apple-green translucent material the most desirable It may have colored veining running through it (tan to brown common).
It is considered the most expensive of the pure (non-patterned) chalcedony group and resembles high quality jade. The color can fade with heat so care must be taken when soldering around the stone.