You can also go for a Diopside (color is chrome green) or Dioptase (color is similar to emerald) which is a semi-precious natural green gemstone; a cost-effective alternative of Emerald. Most Diopside from Thailand are color enhanced i.e. treated with either heat or diffusion with mostly glass filling to enhance clarity, so be sure to get a gemstone certificate which mentions its treatments as well.
You can check out following sites for Diopside:
- http://www.gemrockauctions.com/auctions/chrome-diopside/ (I would prefer this website as it will give you competitive price, though you have to make payment in USD on both the websites).
- http://www.ebay.com/sch/Diopside-/110794/i.html
It is hard to find a cut Dioptase gemstone. Mostly they are sold in rough. However, price Dioptase is expensive than Diopside.
Please consult with Srinivasa, if you can wear Diopside as an alternative to Emerald.