Buying emerald can be difficult for the beginner because there is such a huge price difference between low quality and high quality emeralds. The country of origin has a significant effect on emerald prices as well. When looking at comparable emeralds Colombians will be the most expensive followed by Brazilian and Zambian. Emeralds are found in many other places but these three countries are the top producers and will likely be what most encounter for sale. The reason for the price difference between the countries has to due with the color variations. Colombia produces some of the best pure green hues with just a slight amount of blue. Brazilian emeralds are similar to Colombian but often have a brown or gray secondary color while Zambian emeralds tend to be overly blue.
Low-end emeralds that either have poor clarity or pale color can be found for a few dollars per carat. Light does not pass through these emeralds because they are opaque. They may also have such pale green color that many gemologists would classify the gemstone as green beryl rather than emerald.
High-end Colombian emerald prices start around $1000 to $3000 per carat so you can expect to pay about $4000 for a high quality 2 carat emerald. At this price you should expect to have very good color and reasonable clarity with moderate treatment or oil. Almost all emeralds in this price range will be enhanced with oil, resin, or polymer. This treatment is considered acceptable worldwide and has been practiced for centuries. Above $3000 per carat you start to see emeralds for sale that have little or no treatment and larger sizes.