Tessa spent 2 years in PR for a Jewellery company. During that time, she learnt that diamonds were not a girl's best friend. Emeralds were!
Colombian Emerald or Sandawana Emerald?
The Sandawana Emerald is probably one of the most rare stones in the world so it holds its value well. It is strikingly beautiful, and women, like Liz Taylor and Angelina Jolie, have dazzled many when wearing them. Emeralds are mined in most countries in the world, but two particular types of emeralds stand out - the Sandawana emerald from an area in Zimbabwe with the same name and the Colombian emerald from Colombia.
Colombian emerald tends to be the popular choice as they are more freely available and less expensive. The colour ranges from a yellow green to a very dark blue green. The Sandawana emerald is always a very dark blue green.
Characteristics of Emeralds
Some stones, found in the same mines as emeralds, are a lighter green. These are called green beryl. It is the intensity of the colour which differentiates green beryl from an emerald. The price difference between an emerald and green beryl is significant. This is a result of the rarity of the green coloured stones.
Emeralds are very soft so they break easily and need to be worn with care. In technical language, they have a MOHS hardness of between 7.5 and 8. Should the stone be without inclusions, this would be considered quite strong/hard, but any inclusion within the stone weakens it. Jewelers add oil to the stone to make the inclusion less obvious to the naked eye.
It is the addition of either chromium or vanadium to the beryl stone which makes it green. However, the international standard is that only those stones which are green as a result of chromium are considered to be emeralds.
Basically, Sandawana emeralds are green are a result of chromium while Colombian emeralds are green as a result of vanadium.
The American Jewelry Council has indicated that stones with vanadium are to be considered to be emeralds, but this is not the international standard for the beryllium stone. Stones which obtain their colour from vanadium are less expensive than those which are coloured by chromium. This means that a four carat emerald can be bought in the USA for about $800.
Unusually, whereas prized diamonds have no inclusions, this is not so for this beryllium stone.Whereas an instrument is used to determine the purity of a diamond, the human eye is sufficient to determine whether the green gemstone is to be highly prized for clarity or not. It is extremely rare for an emerald not to have an inclusion. Regardless of this, they are still the most valuable of all coloured stones.
They are valued according to the depth of green color, how pure they are, their weight (number of carats), and brilliance. The way the stone is cut is also important.
Synthetic emeralds have been produced and their chemical and gemological composition is identical to mined stones. Ultraviolet light is used to establish whether stones are mined or manufactured.
Some Facts About Emeralds
|Sandawana Emeralds||Colombian Emeralds||All Emeralds|
These emeralds are the most rare.
These are sold in the USA
If 3 carats or more, greater value than diamonds
Their deep green colour comes from chromium.
Their green colour comes from vanadium
All emeralds have inclusions.
They are mined in Zimbabwe, Africa.
Continuing assassinations and murders in attempts at ownership of various mines.
Inclusions make emeralds soft/weak.
Locations Where Emeralds are Mined
Colombia is the world's leading producer of diamonds, producing between 50% and 95% of the world's total, depending on the year. Zambia is the world's second largest producer. The most recent discovery of emeralds was in the Yukon in Canada.
Emeralds are mined predominantly in Colombia, Zambia, Brazil, and Zimbabwe. However, they can also be found in Madagascar, Nigeria, Afghanistan, Pakistan, Canada, and Russia in small numbers.
Magnificent Emerald Jewelry
The largest mine in Sandawana, Zimbabwe, closed in 2012, leaving another twenty seven mines currently operating.
Initially emeralds greater than three carats were found quite frequently at the Sandawana mine, but that is not so anymore. The norm is now about half a carat.
These stones have a far higher value than those mined in Colombia or elsewhere.
As a jeweller once said, "“The finest emerald I’ve ever seen was a 3-carat Sandawana stone shown me in 1980. It’s owner, an Indian dealer, wanted a mind-boggling $60,000 per carat. But eventually he got it.”
The colour and clarity of the stone have a lot to do with the price that the stone gets in the market place. In the early 80s, when the Sandawana mine production was still in full production, this African emerald was fetching twice the price of emeralds mined elsewhere - $1,600 versus $700 per carat.
Zimbabwean emeralds are green as a result of chromium.
These emeralds saw their peak production in the 50s and 60s, and it's possible that political factors, like UDI and the subsequent takeover by Mugabe, had something to do with the further success of the mines.
Unusually, emeralds in Colombia are mined from sedimentary host rock as opposed to igneous rock. This means that they are far more pure than emeralds found in other countries. Their green colour comes from vanadium, so technically they wouldn't be classified as an emerald in countries outside the USA.
Most of these precious stones are mined in the east Andes mountain range between Boyaca and Cundinamarca. The top producing mines are Coscuez, Chivor, and Muzo, with Muzo being the most important mine internationally as it produces a grass-green coloured emerald.
The very dark green emerald which is so highly prized internationally is only found at great depth in these mines. As a result of their value, there is a large illicit market operating.
Quaqueros (smugglers) search alongside the Río Itoco river in the Muzo valley for stones. They also steal from storage houses where the gemstones are stored before they are cut and polished. During the 80s, there was a civil war (Green Wars) over these stones. There are still conflict and murders, and assassinations are frequent.
The 858 Carat Gachala Emerald
The Mogul emerald was found in 1695 and weighs 217 carats. It was last seen in 2001 when it was sold to an unknown buyer for $2.2 million.
The Devonshire emerald is in a vault at the Natural History Museum in London and weighs 1386 carats. It belongs to the Duke of Devonshire and is from Musa in Columbia.
The Gachalá Emerald was mined in 1967, Gachala, Colombia. It was obtained by New York jeweler, Harry Winston, who donated it to the Smithsonian.
For about three hundred years (until just before WWII), emeralds were highly sought after by royalty, the aristocracy, and the very rich as they signaled high status and incredible wealth. When looking at various diadems and crowns made for monarchs, a high percentage of them were not only set with emeralds but had the central stone as a large emerald (or sapphire).
So how do they compare with diamonds?
Not at all.
Sir Ernest Oppenheimer created an artificial scarcity of the stone in the early 40s by mining them and only releasing a few into the market place. Then he used an American advertising company to create the 'A diamond is forever' campaign.' It was arguably the most successful advertising campaign in history as many a lady is convinced that a man's love can only be demonstrated by a 'valuable diamond.'
An Thriller of an Emerald Story!
Emerald rings range in price from about $300 for a vanadium emerald under one carat to a few thousand pounds in the UK for a three carat chromium emerald. Synthetic emerald stones start from about $15.00 up. It's impossible to differentiate between a natural emerald and an artifical emerald as they are produced using the same minerals as Mother Nature uses.
As human beings, we are drawn to blues (sapphires) as they echo the colour of sea and sky and green (emeralds) because they echo the colour of trees and grass.
Emerald gemstones are used in tiaras, rings, earrings, pendants, and bracelets. Angelina Jolie has worn emerald earrings with matching pendant and Elizabeth Taylor owned some magnificent and very sizable emerald rings and chokers.
Royalty has a preference for blue or green stones for engagement rings rather than diamonds, and it is possible, as the general public begins to realize that diamonds are pretty worthless, that there will be an increase in the popularity of emeralds as engagement rings and dress rings. Currently, they are mostly worn in spectacular earrings and pendants.
Colombian Emeralds or Sandawana Emeralds?
There have been some spectacularly large Colombian emeralds found, and their colour has been as good as those of the Sandawana mines. They also have fewer inclusions. However, there are those who will tell you that the colour of the Zimbabwean emerald is superior, and they still fetch a higher price.
It doesn't really matter where emeralds are mined. Their value is determined according to their colour, their weight (number of carats), and their clarity (number of inclusions).
© 2014 Tessa Schlesinger
emerald admirer on December 11, 2017:
very good hub. well explained.
Clive Williams from Jamaica on November 06, 2016: