Emerald

Most prominent variety of the beryl species.

One of the oldest gemstones used by mankind. Because of its long history we have given emerald significantly more room than most other entries in this dictionary.

Emerald shop

Origin of Name: The word "emerald" is derived (via Old French: esmeraude and Middle English: emeraude) from Vulgar Latin: esmaralda/esmaraldus, a variant of Latin smaragdus, which originated in Greek: σμάραγδος (smaragdos; "green gem"); its original source being either the Hebrew word אזמרגד izmargad meaning "emerald" or "green" or the Sanskrit word marakata meaning "green." The name could also be related to the Semitic word baraq (בָּרָק ;البُراق‎; "lightning" or "shine") (cf. Hebrew: ברקת bareqeth and Arabic: برق barq "lightning"). It is the same source for the names Persian (زمرّد zomorrod), Turkish (zümrüt), Sanskrit (maragdam), Georgian (ზურმუხტი; zurmukhti), Russian (изумруд; izumrud) and Armenian zmruxt.
(Wikipedia: https://en.wikipedia.org/wiki/Emerald)

Synonyms and trade names: none

Can be confused with: other green stones like verdelite (green tourmaline), tsavorite (tsavolite) garnet and peridot. Furthermore there are green Bberyls which owe their colour to vanadium, rather than chromium (like emerald). These stones must not be termed emerald but vanadium Bberyls.

Chromium was firstly suspected to be the colouring agent of emerald by the French pharmacist and chemist Louis-Nicolas Vauquelin in 1798. Around 1920 mineralogists started to suspect vanadium to be another emerald chromophore (colouring agent), which later was verified by Russian mineralogist Alexander Fersman, as well as the German I.G Farben Company, a producer of synthetic gems.

Localities: the most important deposits are in Colombia (Muzo, Chivor and several smaller mines) and Brazil (numerous localities in Bahia, Goyas and Minas Gerais). Also of great commercial importance are several African deposits in Zimbabwe, Zambia, Madagascar and Tanzania. African emeralds are often characterized by cooler tones with a slightly bluish tinge, whereas South American emeralds mostly show a warmer, slightly yellowish green.

More deposits of some commercial importance are located in Asia. Several small mines in Pakistan and Afghanistan produce emeralds of truly fine quality. Unfortunately the production is rather small and because Pakistani and Afghani emeralds have an excellent reputation in some Asian countries, e.g. in India, not many of them find their way to the European markets.
 

In the 1980ies Russia supplied large quantities of low grade emerald, most of which was exported to India where it was fashioned into beads. However, Russia does produce some fine emerald. The deposits are located near the famous alexandrite sites near Malyshevo, Urals.

Finally the Austrian Habachtal (Habach Valley) must be mentioned, as it is one of the oldest sources of emerald known to mankind. The mine is still operative today and the very few stones, that are still being found, fetch very high prices indeed with collectors. In fact, because of the rarity and the historical significance Habachtal emeralds are priced distinctly higher than emeralds of comparable quality from other sources.

In literature hints to several Indian emerald deposits can be found.
However, almost all of the hints dating from before the 20th century are of doubtful value.
It was only in 1943 when the first emerald crystals were found near Ajmer, Rajasthan.

 

smaragd antikschliff - emerald cushion cutsmaragd smaragdschliff (treppenschliff) - emerald cut (step cut)smaragd rund - emerald round

Three Colombian emeralds of outstanding quality

Handling: emerald is hard but brittle and sensitive to pressure. Set, handle and wear with care!
Most stones are treated to improve their clarity (see www.edelsteine.at/gemstone-treatments/). The procedure is legal and accepted by the CIBJO, as long as only colourless substances are used for clarity enhancement.

Attention: sometimes the filling substances will readily be removed by heat or alcohol. Be careful during soldering, dopping, cleaning and recutting or repolishing. Never clean ultrasonically!
Senitive to fluoric acid.

Inclusions: eye-clean emeralds are extremely rare. Because most emeralds are more or less (heavily) included, tolerance towards inclusions is much higher than in most other gemstones. In fact the typical emerald inclusions are sometimes euphemistically called jardin, French for garden.
 

smaragd jardin emerald garden
Typical emerald inclusions (jardin)

In very rare cases emerald displays chatoyancy (cat´s eye effect).


smaragd katzenauge - emerald cat´s eye  smaragd katzenauge - emerald cat´s eye
Two emerald cat´s eyes

Emerald is one of very few gemstones whose origin can often be traced back to the very mine by its inclusions.
Edgy three-phase inclusions consisting of a fluid, a gas bubble and a salt crystal are typical of Colombian emeralds.

Additional brownish redparisite crystals are a sure sign of the Muzo mine, pyrite or apatite crystals of the Chivor mine.

  
Parisite - Muzo                   Pyrite - Civor

Emeralds from Sta. Terezinha de Goyas often show coal-like chromite inclusions. Pyrite inclusions (similar to Chivor) in combination with flakes of biotite and black dolomite are typical for Itabira emeralds (Brazil).



Chromite - Goyas

Habachtal emeralds show coarse needle-shaped hornblende (actinolite and/or tremolite) inclusions. If these needles are thin like hair and bent and sometimes accompanied by garnet crystals, Sandawana in Zimbabwe can be assumed to be the origin. The most conspicuous hornblende inclusions are the bamboo-like inclusions in emeralds from the Ural Mountains, Russia.

  
Sandawana                        Ural Mountains

A peculiarity in its own is the so-called trapiche emerald. Trapiche is the Spanish word for the cogwheel used to crush sugarcane. In this very rare type of emerald coal-like shale inclusions form a pattern resembling the spokes of a wheel.

There are at least four types of trapiche emeralds:


 

Fluid inclusions in the shape of fingerprints are also frequent in emerald. Unfortunately they are not proof of natural origin as many synthetic emeralds also show fingerprints which often have a striking resemblance to those in genuine emeralds.

History: emerald is one of the oldest gemstones used by mankind for ornamental purposes. Curiously enough, up to the sixteenth century, when the Spanish started to bring Colombian emerald to Europe, there were only two known sources, Egypt and the Austrian Habachtal.

India is often named as a third source but since this is not sufficiently documented or backed by archaeological evidence, this claim is considered dubious by many.

Emeralds in ancient Egypt


From about 3500 BC to 200 BC Egypt, thanks to its turquoise, peridot and emerald deposits, was the world's most important supplier of precious stones. The emerald mines where located right in the middle of the desert, far to the south-east of Cairo. The date of their discovery is still controversial among historians. Emerald is first mentioned in a papyrus written by Ptah-Hotep, vizier to Pharao Pepi I (around 2300 BC), but it is all but sure that Ptah-Hotep really meant emerald because the Egyptian word mafek (as well as the greek smaragdos) denoted all green gemstones. In fact many "emeralds" in ancient Egyptian jewellery were later found to be other minerals.

The Egyptian emerald mines were verifiably worked extensively from Greco-Roman to Ottoman age, that is to say from about 330 BC to about 1240 AD. Later emerald was mined sporadically but the mines were forgotten rather soon. In 1816 they were re-discovered by a French adventurer and became famous once again by the name "Cleopatra´s Mines". Today the mines are not profitable anymore and of merely historical interest.

As a rule Egyptian emeralds were small of size and heavily included. Nevertheless, because of the magical powers attributed to them, they were highly sought-after and via the silk route found their way to places as far away as India.

Unfortunately not many Egyptian emeralds have survived. In the British Museums collections of Egyptian, Greek, Etruscan and Roman jewellery there are only two emeralds. One may safely assume that the Egyptian mines never really produced large quantities and that due to the inferior quality most Egyptian emeralds were destroyed over the centuries. Most likely many of them were pulverized and taken as "medicine", particularly in India.

Emerald in ancient India

Beryls, particularly emeralds, might have been known in India even before they were known in Egypt. Unfortunately this theory lacks convincing documentation. Emerald is first mentioned in the Rig Veda, a collection of hymns, rituals and religious as well as philosophical writings, dated 1750 BC to 1200 BC.

In it the Nava Ratna talisman is described. Nava Ratna is Sanskrit, meaning "nine gems". One of those was emerald.

It is, however, doubtful whether there were any Indian emeralds at all because there is ample archaeological evidence along the silk route, e.g. in Taxila, the capital of the Gandhara Kingdom, which extended from eastern Afghanistan into the Punjab, that large quanitites of emerald came to India from Egypt.

In any case, in 1943 emerald was found in the Indian state of Rajasthan. The deposit was rather unproductive. Today the mine is not operative any longer and it is by no means proof of the existence of emeralds in ancient India.

Emerald in ancient Far East

The use of emerald in the Far East is a relatively recent phenomenon. The Chinese used beryls for snuff bottles but its origin is uncertain. Today there is a vivid trade in emeralds, which quite often fetch a higher price in those parts of the world than in Europe or the USA.

In Thailand, a major gem trade hub, it is quite difficult to impress one´s neighbours with a Ruby. So wealthy Thais started to wear large emeralds for which they sometimes pay considerably more than at, say, a Viennese High Street jeweller.

Emerald in Greco-Roman time

A reference to emerald is found in a text fragment of Theophrastus, a student of Aristotle, who lived 372 to 287 BC. Theophrast states that staring at an emerald will improve eye-sight.

Again it is uncertain, if by the word smaragdos he really meant emerald.

Pliny the Elder writes about emerald in his Naturalis Historia, a monumental encyclopedia of 37 books. He lists twelve emerald sources, amongst them the ancient city of Coptos, situated north of Thebes on a caravane route leading past the Egyptian emerald mines.

All other "Eemeralds" mentioned by Pliny, some so large that monuments and pillars were carved from them, obviously are not emerald but other minerals, maybe massive quartz or malachite.

However, Pliny also writes about berylli, which are of the same nature as smaragdi. He says they came mainly from India where they were cut to hexagonal shape by skilled lapidaries. This is a clear hint to the hexagonal shape of all beryl crystals.

In Hellenistic and early Roman times gemstones were hardly ever used as ornaments. Jewellery was mostly made of gold. It was only from the first century AD that emerald, amethyst, pearls and other gem materials started to be used in jewellery. The art of gem cutting was not very advanced and so most emerald crystals were simply drilled along the c-axis and strung to necklaces, often in combination with other stones like amethyst or rock crystal. Gemstone engravings were also quite popular with the Romans and occasionally emeralds and other beryls were used for this purpose.

The Romans got their emeralds from Egypt and, possibly, also from the Habachtal. According to one legend the Roman Emperor Nero possessed a monocle cut from a Habachtal crystal.

Emerald in the early Americas.

When in the 16th century the Spanish conquered the New World, emeralds had been in use for jewellery and ceremonial objects for a long time. In fact Colombian emerald was so popular in Peru, that for at least twohundred years after the Conquista, one spoke of Peruvian emerald. Some historians say that the Muzo mine and maybe other Colombian emerald mines as well, were known since 1000 BC. Colombian emeralds were also found with Brazilian natives, which probably means, that the Brazilian emerald deposits were not known back then.

The Spanish shipped huge quanitities of emerald to Europe. Interestingly enough, there are hardly any emeralds in the Spanish crown jewels. Spanish aristocracy was not really interested in the green gems and swapped them for gold, of which they could never get enough. Many emeralds came to India via the Ottoman Empire and Persia and thus contributed to strengthen the legend of Indian emeralds, which in fact probably never existed at all.

By the way: from 1896 to 1906 the Austrian Habachtal emerald deposits were owned and worked by Emerald Mines Ltd.
During those years the English company mined up to 68.000cts per year. The best material was sent to India for cutting and was marketed as Indian emerald.

When the Portuguese in the 17th century discovered emeralds in Brazil and wanted to market them in Europe, they were faced with the stiff resistance of Spanish traders, who, wanting to protect their monopoly, flatly denied the existence of Brazilian emerald. So the shrewd Portuguese first brought the Brazilian emeralds to their Indian colonies, from where they were shipped to Europe as Indian emeralds, the latter having an excellent reputation even though they probably never existed…


Worth knowing: there are several legendary emerald objects in the world. Most of them were found to be made of other minerals in the course of time.
One of these famous objects is the Sacro Catino in the Cathedral of San Lorenzo in Genoa, Italy. The bowl of 36cm diameter and a height of 12.5cm was brought to Europe during the first Crusade. Legend says it was given to King Solomon by the Queen of Sheba, that it was part of King Herod´s table decoration and found its way to the last supper, where Christ himself drank from it.

Today we know that the Sacro Catino is made of glass, mass-produced in Rome during the first or second century BC and that it most likely is not the Holy Grail ;-)

When Napoleon conquered Genoa at the end of the 18th century, he sent the bowl to Paris where it was identified as glass. In 1815, at the Congress of Vienna, it was decreed that the bowl had to be returned to Genoa. On the way back it broke, but was repaired skilfully. Until today some people in Genoa hold the opinion, that Napoleon only stole a glass replica and that the real Sacro Catino is kept in a secret place in Genoa.



Probably the most famous object of them all is the so-called Emerald Buddha, a figurine of 66cm (including throne), which is kept at Wat Phra Kaeo temple in the Grand Palace in Bangkok. It is of unknown age and said to have been carved by a celestial sculptor. Found in 1464 in the northern city of Chiang Rai, it made its way to Bangkok where King Rama I had a temple built for it in 1785.

The Buddha is not made from emerald. The Guide Book says it is carved from a single block of jade, a statement which is doubted by gemmologists. Because of the sacred nature no mere mortal – except for selected priests - is allowed near it, so we might have to wait for confirmation for some time to come.

Last but not least, the treasury of Viennas Imperial Palace houses a truly singular specimen. The largest emerald carving of the world, made from a single crystal, in the form of a small vessel weighing 2680cts.
The Colombian emerald crystal came into possession of the Habsburgs at the beginning of the 17th century. In 1641 Emperor Ferdinand III asked the famous gemcarver Dionysio Miseroni to cut it, which took almost two years.

Such pieces are called mirabilia, marvels, and their sole purpose was to demonstrate the Emperor´s imperial power and wealth. When in 1645, towards the end of the Thirty Years´ War, Ferdinand wanted to take a loan on the vessel in Genoa, to finance the war, local jewellers refused to lend money arguing that they did not trade in objects that large.

The Grand Duke of Florence allegedly offered to swap three tonnes of gold for it. Why the deal did not happen we don´t know.

 

Emerald shop

 

Gemmological Properties of Emerald

Formula:
Be3Al2(Si6O18)
Crystal system:
hexagonal
Mohs hardness:
7.5-8
Specific gravity:
2.60-2.90
Refractive index:
birefringent 1.564-1.602
Max. Birefringence:
0.007
Dispersion:
0.014
Pleochroism:
distinct, green, bluish green / yellowish green
Luminiscence:
inert
Lustre:
vitreous
Cleavage:
imperfect
Fracture:
brittle, conchoidal
Colour:
green, yellowish green, (very slightly) bluish green