My wife loves green gemstones, but felt that emeralds generally have a pastier, paler look than tourmaline or tsavorite. Here is a picture of her prized stones.
The one in the necklet is a tourmaline and the one in the ring is a tsavorite. Tsavorite is a slightly softer stone but has a slightly higher refractive index than tourmaline with both being generally higher than emerald.
But as in Heathos post stones can come from a very different location on earth and therefore present in a wide variety of colours, hardnesses and RIs so that these physical properties can overlap making identification difficult.
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