Tag Archives: emeralds

What makes Austrian emeralds so rare and unique?

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A lot that stood out to me around the salerooms last week was this this pretty cluster ring. Sold at Woolley & Wallis and described as ‘An unusual emerald and diamond ring, late 19th century,’ this ring was set with a principal oval emerald cabochon and surrounded by cushion shaped diamonds.

Accompanied by a certificate from Gemmological Certification Services, the emerald’s origin was stated as Austrian, with indications of moderate clarity enhancement. The unusual factor, then, in this lot was the origin of the emerald! Usually at auction we can see Zambian (increasingly!) and the historically favoured Colombian emeralds. An emerald from an altogether different locale in Austria, was an unusual thing indeed!

This ring was estimated at £800-1200 and reached a hammer price of £2,016 inclusive of fees. We would be looking at an insurance valuation of £6,000-8,000, subject to change upon physical inspection of the piece.
This ring was estimated at £800-1200 and reached a hammer price of £2,016 inclusive of fees. We would be looking at an insurance valuation of £6,000-8,000, subject to change upon physical inspection of the piece.

The Austrian emerald deposit lies in the Habachtal Valley.  Located in the Hohe Tauern National Park, and a favourite with hikers, this valley is known for its emerald deposits and rich mining history!

Emerald Necklace from the Treasure of Vaise. 3rd Cenury AD
Emerald Necklace from the Treasure of Vaise. 3rd Cenury AD

The first written reference to the Habachtal emeralds is in 1797, although in 1992, Roman jewels in the Treasure of Lyon-Vaise included emerald necklaces and earrings set with emeralds mined in the Habachtal Valley. These pieces are thought to have been buried for fear of Germanic raids and the coins allow its burial to be dated to after AD 258.

The first international appearance of Habachtal emeralds was in 1861 at the London World Industrial Exhibition. Mining operations by Samuel Goldschmidt began in the early 1860s, and he sold these crystals from his Viennese storefront. Following his death in the 1870s, the mines were ran by various English companies until around 1913 – purportedly selling the stones as ‘Indian emeralds’ “because the deposit was not known to most of the people in gem trade and would have sold for a much lower price.” (Laing Antiques).

The ring above dates to this later period of English owned mining in the Habachtal area and could well have been originally sold as an ‘Indian’ emerald. Identifying features for Habachtal emeralds are typically heavily included, with “highly-ordered graphite, and extremely water-rich melt inclusions.” (Rainer, 2020). Sold as Indian emeralds  and typically assessed as lower quality owing to their multiple inclusions, examples of Habachtal emeralds are not frequently identified! Below is an example of a diamond and 2.10ct Austrian emerald ring currently retailing for €14,500.

an example of a diamond and 2.10ct Austrian emerald ring currently retailing for €14,500.

Habachtal emeralds are still mined in the present day, although it much lower quantities than the late 19th century. The yield is typically small scale and is reserved for collectors of specimens, much like the example below sold at Christies in 2023.

This example of a Habachtal emerald in its original matrix was sold at Christies in May 2023 and achieved a hammer of £2,394 inclusive of fees against a £2,000-3,000 estimate.
This example of a Habachtal emerald in its original matrix was sold at Christies in May 2023 and achieved a hammer of £2,394 inclusive of fees against a £2,000-3,000 estimate.

To arrange your own jewellery valuation, call us on 01883 722736 or email us on [email protected]

Emeralds

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These luscious green stones are first mentioned around 3500 BC – and were treasured for their beauty and have over the years been attributed with bringing good health, love and romance and were considered the gem most close to the Deities. An early believer and emerald hoarder was Cleopatra who started two emerald mines in her native Egypt on the slopes of Mount Smaragous (from which we eventually get the word ‘emerald’). The Romans preferred them to diamonds and in the 17th century the Indian Moguls carved prayers and blessings on large flat cut emeralds.

A fine emerald exhibiting all the required qualities, and is in addition, over 12 carat

After the Egyptian mines were exhausted smaller deposits were exploited in India and Austria, but it was in the mid 1500’s when Spain started colonising South America and Columbia in particular, that they became far more readily available and they were and still are considered to be the best real gem quality stones. Columbia alone supplies about 60% of the world’s supply but since the 1950’s small quantity of good quality stones has been coming from Brazil, Zambia and the very sought after Sandawana emeralds from Zimbabwe. Pakistan, Afghanistan, and Madagascar also have reasonable reserves but supply from all these countries is spasmodic due to political grief and wars.

Emerald of a poor colour and heavily flawed stone

Their comparative rarity has maintained their popularity over the years and in 2011 Elizabeth Taylor’s emerald collection was sold for about $25 million and more recently an 18 carat emerald and diamond ring belonging to Angelina Jolie sold for over $5.5 million – setting a record of over $300,000 per carat.

So what are emeralds? They are members of the Beryl family which includes the pale blue Aquamarine and the pale pink Morganite amongst others. They are a relatively ‘soft’ stone measuring 7.5 on the gem hardness scale as opposed to a diamond at 10, so they fracture, chip and scratch quite readily. With a diamond it is both good colour and clarity that enhance value – with emerald it is mostly about colour as it is virtually unheard of to find a totally ‘flawless’ stone. The most prized emeralds are those with a rich dark to medium green tone and preferably with good even ‘saturation’ of colour and translucence throughout the stone.

The palest green that would still be classified as emerald

The first photograph shows a fine emerald exhibiting all the required qualities and is in addition a whopper at over 12 carat. The second photograph shows a poor colour and heavily flawed stone, and the third photograph shows the palest green that would still be classified as emerald.

In the fourth photograph the stone on the left is about 3 carats and good colour and decent clarity, the one on the right is over 4 carats and pretty pale and noticeably flawed. The ring on the left fetched twice as much as the other one at auction recently. That’s the difference, both visually and value wise between a ‘good un’ and a ‘bad un’.

Left: about 3 carats and good colour and decent clarity
Right: over 4 carats and pretty pale and noticeably flawed.

Pale green stones do not achieve the title of emerald and are called green beryls and are of relatively small value. For centuries, surface scratches and fissures which nearly all emeralds suffer have been ‘oiled’ which fills the cracks and because the oil is colourless it ‘evens up’ the colour. More recently polymers and resin have been used instead of oils and because they are often coloured green they are considered to represent unfair and unethical enhancement. This is described as ‘modern’ treatment and should be avoided. The long established methods are described as ‘traditional’ and as long as it is not excessive, is nowadays acceptable. Because of this, any proposed purchase of a serious emerald should only be considered if the stone has a laboratory certificate grading the extent and type of enhancement. There are generally four grades of enhancement – none (very rare), insignificant (desirable), minor (acceptable) and moderate )just about ok)) and significant (to be avoided).

Internal inclusions, called ‘jardins’ in the trade, are expected and accepted as normal. They range from feathery/mossy looking gas or liquid filled ones to internal fractures and fissures. The range and type of inclusion can be interpreted by a laboratory test and they can ascertain from which area and country the stone originates. The techniques now available to remove or reduce inclusions in a diamond involving laser beams and high temperature treatments cannot be used on an emerald due to its comparative softness and different crystal structure, so whatever defects get moulded in to the emerald at the time of formation remain with it.

A fine quality and colour emerald of decent size – say 3 carats and over – is far rarer than a quality diamond of the same size, so, in my opinion, should be of higher value. That’s not the case, however, and although Angelina Jolie’s stone fetch over $300,000 per carat, there are plenty of diamonds around priced at over $500,000 per carat. £5000 per carat would buy you on the retail front a very presentable emerald but the same carat price would get you a diamond pretty far down the scale in colour and clarity.

So with that in mind, could an emerald be a good investment? As with most categories of speculative investment always go for the best you can afford – go for colour firstly, clarity secondly and size thirdly, and bearing in mind its comparative fragility, treat it gently and have the stone and its mount checked by a jeweller regularly.