Aussie Sapphire

The July birthstone is well known as Ruby but for those looking for an unusual alternative, the ancient gem Carnelian may be of interest. 

(Image from OldenWisdom)

Gemmology Matters:  Carnelian is a cryptocrystalline form of quartz and is a translucent, semiprecious variety of chalcedony that owes its red to reddish brown colour to the presence of dispersed hematite (iron oxide) within the silica mineral.  As with other varieties of chalcedony, hardness is 7 on the Moh’s scale.  The stone is closely related to Sard which is a brownish colour – see here for more information.

Most commercially available carnelian has undergone some enhancement treatment.  Yellow/brown chalcedony has been routinely heat treated at low temperatures to create red carnelian stones for many centuries.  Carnelian is mostly cabbed or formed into beads and is an inexpensive stone with warm and attractive colour.

Mythology and Lore:  Carnelian has been valued for many centuries and is mentioned as a birthstone in ancient Arabic, Herbrew and Roman tables.  The stone is named after the Latin word “carneus” for “flesh” because of its reddish colour. 

As a healing stone, carnelian may be used to treat blood disorders, menstrual problems and back pain.  Continuing with the theme, carnelian has been thought to help with infertility and may be worn to enhance passion.  Carnelian is associated with the zodiac signs of Leo and Virgo.

Like other forms of chalcedony, carnelian is well suited to intaglio work, engraving/carving and for seals.  This fine example of a seal ring depicts an actor holding a tragic mask and is held in the British Museum (image from VRoma, copyright Barbara McManus 1999)

This second example is a carnelian carved gem inscribed in Greek – this one is from Hixenbaugh Ancient Art and may be purchased through their website if you would like to own a piece of history from Ancient Greece.

Alternatives in Orange/Red: Obviously the king of red gems is Ruby but there are many other alternatives in red.  For transparent gems, red spinel is increasingly popular and some species of garnet provide a range of colours from red to orange.  Carnelian is generally more translucent than these alternatives and does have a “waxy” look that is quite distinctive. Carnelian with its affordability and warm colour should give collectors a reason to have at least one example of this ancient gemstone.

Links of Interest:

• Bernardine Fine Art Jewelry – article on Carnelian
• Carnelian – The Magic of Rock & Stones by Controverscial.com
• Mindat .org entry on Carnelian

Unforunately, we have no carnelian listed online although we do have some small cabochon carnelian in stock – if you want reddish orange, we also suggest some natural colour zircon. Both gems are very affordable so why not get some of each.

Cheers for now from Andrew and Leah Lane (Aussie Sapphire).

The birthstone for January is generally acknowledged to be Garnet. Unlike some other months, there are few alternative stones for January although some sources list emerald as the “mystical stone” for January.  However, garnet is a very versatile gemstone in its own right with a beautiful range of colours available.

Since we have already covered Garnet in our usual “Gem of the Month” format, we will explore some of the varieties of garnet in this month’s article.  An example of one of the more unusual varieties is tsavorite seen in the photo at left from Palagems in their Tsavorite Buying Guide.

Garnet is a group of minerals with similar chemical composition, physical properties and crystal structure.  There are six species of garnets recognised although many gems lie on a substitution scale between species making a positive identification somewhat challenging in many cases.  See the Garnet Factsheet on Mineral Miners for more discussion on garnet species and how to distinguish them.

• ALMANDINE:  Colour is typically a deep, rich red – less valuable specimens have more brown.  Sources:  Brazil, India, Madagascar, Sri Lanka, U.S. in Arizona, Idaho, New Mexico, Utah, Arkansas and Kentucky.
• PYROPE:  Colour is usually deep, rich red or variations on this.  Sources:  Australia, Czechoslovakia, South Africa – Zimbabwe and Mozambique.
• SPESSARTITE:  Colour is ideally bright orange but ranges from reddish orange, red, reddish brown, to brown.  Sources:  Brazil, Namibia, Pakistan, Sri Lanka, US.
• ANDRADITE:  Colour usually ranges from green, yellowish green to greenish brown and may occur in black.  This species includes the highly sought after demantoid garnets.
• GROSSULAR:  This species ranges widely in colour from colourless to black with almost all colours in between (red, green, pink, yellow, etc).  This species includes the rare and valuable tsavorite garnets.
• UVAROVITE: This quite rare species of garnet is dark green and often found as fine crystal clusters (sometimes referred to as drusy because of the small crystal formations).

For more reading on this, I recommend the Garnet page on the Gemology Project – this is a new resource associated with the Gemology Online forum so it is highly recommended for anyone interested in gems.

Due to the complexity of the garnet group, there are quite a number of individually named gem varieties.  Here are just a few:

• HESSONITE: this garnet falls into the grossular species and occurs in yellow, orange and brownish colours.
• RHODOLITE: This rose-red to purple garnet is part-way between Almandine and Pyrope – closer to pyrope than the Mozambique type garnet which is also a pyrope-almandine garnet of a deep red shade.
• TSAVORITE: Medium, intense green to slightly yellowish green.  This rare and valuable gem is found in Kenya around the Tsavo National Park area for which it is named.
• DEMANTOID:  Another highly sought after gem – the best examples will show intense green colour and “horsetail” inclusions.

The commonly found red garnet (likely of pyrope-almandine type) are very affordable and used in jewellery all around the world.  A range of these in calbrated sizes are available in our online shop for those looking to use them in jewellery at the more budget end of the scale.  A little higher up the scale is rhodolite and spessartite.  Spessartite in particular is becoming very popular and with a current shortage of rough, they are certainly not a cheap option.  For those who want only the best, we suggest you consider the more rare varieties of garnet such as demantoid, tsavorite or colour change garnets (including the new blue varieties from Madagascar).

 A classic example of a demantoid garnet from the Ural Mountains in Russia – clean except for the diagnostic “horsetail inclusions” and available from Mineral Miners.

The picture at right shows some spessartite cabochon cut from rough we sourced from Nigeria.  We have spessartite rough available online now and we hope to list some of our faceted and cabbed gems as soon as possible.  These gems can show some real fire and make fantastic pieces of jewellery.

I hope this article has inspired you to consider garnet for your next gemstone purchase – there is certainly something for everyone in this fantastic range of gems.

The modern birthstone for December is Turquoise (traditional or alternative birthstones include blue topaz, zircon and tanzanite).  The example at left shows a beautiful sky blue colour with a dramatic black diagonal slash – from Aztec Moon.

Gemmology Matters:  Turquoise is a hydrated copper-aluminium phosphate with the chemical formula CuAl₆(PO₄)₄(OH)₈·5H₂O.  Turquoise is a cryptocrystalline opaque mineral which is rare in gem quality.  Colour ranges from white through various blue colours to a yellowish green with the most valuable types usually considered to be a pure sky or “robin’s egg” blue with little green tone and even colour.  Colour type depends on the relative amounts of copper and iron in the stone with copper producing blue colour and iron producing green.  Although uniformity of colour is prized in turquoise, it is often found with brown/black veining or marks running through the stone – known as “Turquoise Matrix”, these types are usually worth less but may be considered more attractive by some buyers.

Turquoise is mined in the Southwestern United States, Iran, Tibet, and China.  Turquoise is usually found in dry regions and in association with copper deposits.  Particuarly in the USA, it is often mined as a by-product of copper mining.  Photograph at left shows a piece of turquoise from Nevada (image from Skystone Trading).  Australia is not a major source of turquoise with only small deposits found in northern Victoria, in the Narooma-Bodalla region of the New South Wales south coast, and at Amaroo station in the Northern Territory (Australian Museum).

Turquoise in its natural state is relatively soft at 5 to 6 on the Moh Scale.  It can be susceptible to damage or discolouration if exposed to prolonged sunlight, skin oils or chemicals in perfumes, cleaning agents, etc.  In order to protect against this, many turquoise gems are sealed with oil or wax.  A more radical form of this treatment is the creation of “bonded” or “stabilised” turquoise by impregnating the stone with epoxy or plastics under pressure.  Some turquoise is sold as “reconstituted” where small fragments of stone are ground and then bonded together to form a new stone – be aware that these types may include “filler” material and/or be dyed.  Imitations are also frequently used – the most common being white howlite dyed to imitate the blue of turquoise.  The cheaper turquoise used in beads or low-cost silver jewellery is usually heavily treated or may actually be imitation.  Very fine quality turquoise is rare and will command a high price – these stones should be verified by an expert.

Mythology and Lore:  Turquoise is among the worlds oldest known gemstones – many ancient civilisations valued it highly.  The name Turquoise is derived from the French “Pierre Turquois” meaning Turkish Stone as it was thought the gem came from Turkey.  Actually, the gems reaching Europe at the time came via marketplaces in Turkey from Persia (now Iran), where some of the oldest known turquoise mines are located.  In Persian, Turquoise is known as “Ferozah”, meaning victorious and it is the national gemstone of Iran to this day.

Ancient examples of its use survive to this day and it may seen in some of the most famous archeological artifacts.  The gold burial mask of Tutankhamun is heavily inlaid with gemstones of which turquoise features prominantly. The Aztecs also used the stone heavily and a number of examples of this work may be seen in work dating back to the time of Montezuma.

Image at left is of Tutankhamun’s Burial Mask – courtesy of the Egyptian Museum.  Image at right is of an Aztec double-headed serpent with turquoise mosaic – see the British Museum image collection of artifacts from Montezuma’s Treasure.

Many Native American peoples used the stone as a protective amulet - it is often associated with the sky and wind.  It is said that Apache warriors believed wearing  turquoise would improve their hunting prowess.  Turquoise was generally believed to bring happiness and good fortune to all and in fact, it did bring great fortune to the Anasazi people who mined the stone due to the high demand for it from other areas such as Mexico. 

The typical Native American turquoise set silver jewellery is a relatively modern development (thought to date from the late 1880′s) – traditional pieces were more likely to use turquoise as beads, inlay or mosaic on natural materials such as wood and carvings. 

However these days, the use of silver to complement the unique beauty of turquoise is closely associated with southwestern American culture and the popularity of this style of jewellery has spread worldwide.  This wonderful example of a handwrought silver bracelet is by Harry H. Begay and is available from Chacadog.com – it is not cheap but the quality of the workmanship and materials deserve no less.

Alternatives in Blue:  Blue is an extremely popular colour for gemstones and there are a range of other gems in blue or blue-green.  For transparent gems, we suggest blue topaz, blue zircon or aquamarine.  Although sapphire from our mine tends to be more saturated in colour, it is possible to buy sapphire in these sky-blue shades as well.  While topaz and zircon are reasonably affordable, you will pay quite a bit more for sapphire or for aquamarine of good (not washed-out) colour.  Blue alternatives in opaque gems might include chrysocolla, agate, lapis lazuli and other similar stones.

Links of Interest:

• Wikipedia article on Turquoise (very detailed)
• Bernardine Fine Art Jewelry – article on Turquoise
• ICGA Gem by Gem – Turquoise
• About Turquoise by Skystone Trading – focusing on American turquoise with lots of photographs of different types.
• GIA Library – Featured Gem: Turquoise

Hope you enjoyed this article on turquoise – stay tuned for the next gem of the month.

cheers from Aussie Sapphire

Yellow topaz is also known as the modern birthstone for November.  Although now probably overtaken by the more commonly used Citrine, Topaz is a particularly lovely gemstone which is deserving of more recognition in its “precious” form.

Photo at left from is a good example of Imperial Topaz from Mineral and Gemstone Kingdom

Gemmology Matters:  Natural Topaz is a fluro silicate with the chemical formula Al₂SiO₄(F,OH)_2 .  It is found in a variety of colors including brown, red, orange, pink, sherry, yellow as well as colourless.  Often the shades from yellow through to red are termed “Precious Topaz” with particular colour combinations described as “Imperial Topaz” – those gems denoted as Imperial and the very rare red varieties command the highest prices. The definition of Imperial Topaz colour (reddish-orange?) can be quite complicated – see this Gemology Online thread for more discussion on this subject. 

 This example of a sherry coloured topaz crystal is from John Betts Fine Minerals (Gem Crystals catalogue) - this specimen is from Pakistan and shows the hexagonal crystal habit of topaz very clearly.

Green and blue topaz are naturally very pale, the very bright colours often found in jewellery today are the result in irradiation treatment - Sky Blue, Swiss Blue and London Blue are names used by the gem trade to refer to the depth of color.  See our Blue Topaz article for more information.  Please note that surface colour coatings are becoming more common in Topaz – starting with the multi-colour version of Mystic Topaz, but now also used to create other colours such as pink.  Gems treated in this way should be treated with care to avoid damaging the colour coating.  These types of gems should be far cheaper than naturally coloured stones so be wary when purchasing brightly coloured Topaz and ask about enhancement treatments first.

The principal sources for topaz is Brazil – also found in Sri Lanka, Russia, Australia, Africa, Mexico and Pakistan.  Topaz is an excellent gemstone for jewellery with a hardness of 8 – although it has perfect cleavage which may present some danger when setting in jewellery.  For this reason, topaz should be treated with care and protected from hard knocks.

Mythology and Lore:  While the blue variety of topaz is for those born in December, yellow topaz is the modern November birthstone.  Topaz may be given to celebrate the 4th, 19th and 23rd wedding anniversaries.

Most of the mythology for topaz relates to the yellow variety as natural blue topaz is quite rare and pale in colour.  The Egyptians believed that topaz was coloured with the golden glow of Ra – the sun god.  The importance of Ra made topaz a very powerful protective amulet for the faithful.  This link with the sun was also found in ancient Roman culture where topaz was associated Jupiter, also a God of the Sun.

Topaz was once thought to strengthen the mind, increase wisdom, and prevent mental disorders.  It was also thought to guard against sudden death.  Legend says that topaz has the power to dispel all enchantment and help improve eyesight. The ancient Greeks used the gem to increase strength and make its wearer invisible in times of crisis.  Used in medicine in ancient time, topaz was said to cure insomnia, asthma, and hemorrhages.

This imperial topaz photograph is from the Palagems Topaz Buying Guide which also has some excellent information on the famous Ouro Preto mine in Brazil (see link below).

Alternatives in Yellow:  The range of colour in Precious Topaz brings to mind the amber gold of fine cognac, the blush of a ripe peach and all the colours of a setting sun.  While its cheaper cousin, Citrine, is commonly used these days and is an alternative November birthstone, it is slightly softer and does not have quite the complexity of colour that is present in a particularly fine Topaz.  Sapphire is also found in yellow – while beryllium treated yellows now abound in the marketplace, a fine golden yellow sapphire of natural colour can command very high prices.

Links of Interest:

• Bernardine Fine Art Jewelry - article on topaz
• ICGA Gem by Gem article – Topaz
• Pala Gems – Imperial Topaz Buying Guide
• Excerpt from Secrets of the Gem Trade (R.W. Wise) – Topaz, Visiting the Mine
• Mineral and Gemstone Kingdom – Topaz
• Wikipedia article on Topaz

Aussie Sapphire does not currently have any topaz in stock – we do have a small supply of good yellow sapphire (natural and basic heat only – no beryllium treatment).  None of this is currently listed but we invite you to contact us directly if you are interested.

cheers for now from Aussie Sapphire

The theme for October birthstones is colour and lots of it!  We have already covered Opal with its “play of colour” in a previous article.  This time, we look at the alternative birthstone for October: tourmaline – the Rainbow Stone.  (Photo from ICGA article)

Gemmology Matters:  Tourmaline is truly a fascinating gemstone. Tourmaline is a very complex group of minerals but may be described as a complex aluminium borosilicate where colour is caused by presence or absence of various metal ions (Fe, Mn, Cr, V, Ti and Cu) in the crystal structure.  Hardness is 7 to 7.5 on the Moh Scale making it suitable for most jewellery applications.  Commonly found as prismatic crystals (trigonal-hexagonal), often with vertical striations along the prism faces.

While it can have fantastic colour, strong dichroism and sometimes unstable crystal structure means that tourmaline can be quite challenging for the gem cutter. Cutting orientation is very important so that the faceted gem displays the best colour possible.  Where the colour is too dark looking through the crystal (referred to as “closed C-axis”), they may be cut in elongated shapes (where the A-B axis shows better colour).  Some types can be unstable during the cutting process – if not handled carefully, the stone can crack badly while being faceted.

A fascinating property of some types of tourmaline has led to it being used for scientific and industrial purposes.  The piezoelectricity effect occurs when an electrical charge is induced by applying pressure to a tourmaline crystal in the direction of the vertical crystal axis – this can be used in pressure measuring equipment and other scientific applications.  A similar effect called pyroelectricity occurs when the crystal is heated yielding a positive charge at one end of the crystal and a negative charge at the other.

Tourmalines are mined everywhere in the world with important commercial deposits located in Brazil and parts of Africa.  Other notable locations include Sri Lanka, Madagascar, Pakistan, Afghanistan and the USA. The price range for gem quality Tourmaline varies almost as much as its colour with some rare and sought after varieties bringing extremely high prices.  The recently discovered Paraiba source in Brazil with its intense neon blue coloured stones produces gems that are particularly sought after.

These photos show a small selection of mixed colour tourmaline from Nigeria.  Dont have much of this material left now so keep your eye on our online shop for the last few bits.

Mythology and Lore:  Tourmaline is known as the “Rainbow Stone” from an ancient Egyptian legend: on the long way from the Earth’s heart up towards the sun, Tourmaline travelled along a rainbow, collecting all the colours of the rainbow on its journey.  The name derives from the Sinhalese (Ceylon) word “tura mali” meaning stone of mixed colours. 

The Empress Dowager Tz’u Hsi, the last Empress of China, was a great collector of pink tourmaline and rubellite.  She imported tons of tourmaline from Southern California in the early twentieth century, creating a gem rush in San Diego during the period.  She loved pink tourmaline so much that she was laid to rest on a pillow carved from this gemstone. 

Tourmaline is the birthstone for the month of October and is associated with the zodiac sign of Libra.  Legend says tourmaline inspires artistic expression, enhances intuition, increase self-confidence and amplify one’s psychic energies.  Tourmaline may be used to neutralize negative energies, dispel fear and grief, and to aid in concentration and communication.

Alternatives in Multicolour:  Tourmaline is unique for its range of colours and gems where more than one colour is displayed.  While tourmaline may be found in many colours which are also represented by other gems, it is the bi- and multi-coloured varieties which are difficult to find elsewhere in the gem world.  Sapphires may show this bi-colour character (called “parti” in Australia) but generally the colours tend toward the blue-green-yellow and do not display the sharp boundaries of significantly different colours seen in some tourmaline.

Links of Interest: 

• Previous Blog article on Watermelon Tourmaline
• ICGA Gem by Gem article on Tourmaline
• Bernardine Fine Art Jewelry article on Tourmaline
• Wikipedia article on Tourmaline
• Pala Gems - Tourmaline Buyers Guide

Hope you enjoyed this article on Tourmaline – truly worthy of a book but we’ll leave that job to someone else.  We still have some nice pieces of tourmaline rough in stock as well as some nice cut gems in a variety of colours (including nice emerald greens and intense pinks). Please enquire at any time about these. 

Cheers for now from Aussie Sapphire

The modern and traditional birthstone for September is Sapphire – covered in a previous article.  While sapphire is our primary interest, we also enjoy and appreciate the many alternative birthstones for each month.  The mystical birthstone for September is Agate - a stone of amazing variety and colour.

Gemmology Matters:  Agate is the name given to a very large family of quartz gemstones of which Sardonyx – subject of our last Gem of the Month article – is a member.  Agate is a type of chalcedony or fibrous cryptocrystalline quartz (SiO2) and is found in a variety of colours, may be translucent, transparent or opaque and has a hardness of 6.5 to 7. 

Agate used for ornamental or in jewellery is often treated by dying to enhance or alter colour.  Since quartz is a very abundant mineral on Earth, agate is quite inexpensive.  Some particularly attractive and unusual varieties may command a higher price but this stone is still a great way to start an affordable gem collection.  Moss agate and Plume agate are two varieties which are priced higher due to beauty and demand.

Agate is found throughout the world in a huge variety of form.  Probably every country has a particular area that yields stones of a particular type of beauty and Australia is no exception.  Here in Queensland, there is an area (surprisingly called “Agate Creek”) which is rich in these gems which are available for anyone to find for just the price of a fossicking licence and a few hours of digging.

Mythology and Lore:  The name agate derives from the Greek for stones found on the Achate river in Sicily.  Agate has been used for thousands of years – examples have been found with other Stone Age relics dating back to as early as 20,000 BC.  Agate was also used by early civilizations for talismans, amulets, seals, rings and vessels.

People in medieval times wore agate to bring God’s favor, enhance persuasiveness, increase courage and strength and protect against danger.  Agate was also used to promote pleasant dreams and cure insomnia.  Early Greeks made amulets of agate for protection from the elements of the sea.

Agate is associated with the zodiac sign of Gemini and for those born in the month of May.  Agate may also be given to celebrate the 12^th wedding anniversary.

Alternatives for Agate:  Due to the extremely wide variation in colour and form, there is really no alternative for this unique gem.  Added to this, the fact that it is very affordable, there is no excuse for you not to have at least one attractive piece in your collection. 

Links of Interest:

• Bernardine Fine Art Jewelry – article on Agate
• Mineral Miners – Fact sheet on Agate
• Wikipedia article on Agate
• Agate on Mindat.org – Minerals Database
• Agate Creek area - Australian Gem Gallery
• Fossicking information for Agate Creek - Queensland

Cheers for now from Aussie Sapphire

And remember, if you are looking for the traditional September birthstone of sapphire, we can give you lots of choices in our online shop.

This month’s gemstone is Sardonyx, the alternative birthstone for August (photograph at left from Thaigem).  The modern birthstone is peridot (covered in a previous article) but sardonyx has an ancient history and is a fascinating stone.

Gemmology Matters:  Sardonyx is a variety of onyx which is a form of banded chalcedony (cryptocrystalline quartz or SiO2) or agate. The name sardonyx derives from the word ‘sard’ and ‘onyx’ relating to the striped or banded appearance of layers of white, grey or black interspersed with reddish brown.  As a variety of quartz, sardonyx has a hardness of 7 and is reasonably strong although prone to chips and scratches.  The durability of sardonyx, combined with its attractive coloured pattern means that it is frequently used for beads and brooches.

Sardonyx has been mined in India for thousands of years and it remains a major source of this ancient gemstone.  Other locations include Russia, Pakistan, USA, Germany, Brazil, Mexico, Czechoslovakia and Africa.  Sardonyx is a relatively inexpensive stone and may be found in large sizes.  Stones with bright orange-red, reddish brown and white bands are popular.  Natural sardonyx is rarely found commercially with enhancement treatments common - usually dying or staining to intensify or alter colour.

Mythology and Lore:  According to Pliny, sard is named after Sardis where that mineral is found. Onyx is named after the Greek word for ‘nail’ because its veined appearance resembles a fingernail.  Sardonyx was highly valued in Rome, especially for seals, because it was said to never stick to the wax.

The ancient Greeks and Romans were very fond of sardonyx and believed it could bring courage and victory. Sardonyx was often engraved with images of relevant gods (such as Ares, Hercules or Mars) and carried into battle by soldiers who believed they would become as brave as the figures carved on these talismans. Away from the battlefield it was believed to lend the gift of persuasiveness to orators and leaders.

Sardonyx cameos were very popular in Roman times.  The example at left depicting the coronation of Constantin the Great is from the ‘Road to Byzantium exhibition’ by the Hermitage Rooms.  See the Vroma website for more images of these ancient pieces in cameo work.  Sardonyx has been used for this type of jewellery for centuries where the different bands of colour carved in relief highlight the image against the background. 

 The popularity of sardonyx for cameo jewellery lasted well into modern times although the designs still tend to draw from ancient themes.  The piece on the right has a more contemporary feel about it although the carved design is still quite traditional in style.

Sardonyx is said to calm the mind, aid communication and promote happiness in marriage and relationships.  An old rhyme listing birthstones and their associated traits claims that:

The August maiden, with sweet simplicity
wears Sardonyx, gem of felicity.

Alternative Stones:  Within the agate family, there is a huge variety of form and pattern.  Many varieties exist and are named for origin, colour or pattern.  Sardonyx and other agate varieties possess a unique beauty that cannot be matched by any other gemstone.  There is no real alternative to this gem.  The affordability of sardonyx means that anyone can add a piece to their collection.

Sources and Links of Interest:

• Article on Sardonyx by Thaigem.com
  ICGA Gem by Gem article on Onyx
  Signets, Amulets and Jewelry Gemstone Engravings Over the Passage of Time (article by Peter Henselder on Ganoskin)
  Add More Color To Your Life article on Chalcedony
  Mineral and Gemstone Kingdom – article on Chalcedony

Hope you enjoyed this month’s article.
That is all for now from Aussie Sapphire

Red, the colour of love and passion, is also the colour of Ruby - the gemstone for July.  One of the most valuable of gems, a fine natural ruby is extremely rare and priced accordingly.

Gemmology Matters:  Unlike many gems, ruby is only ever one colour – a pure red.  The reason for this is that ruby and sapphire are varieties of the same mineral, corundum or Al2O3 - only red corundum is called ruby while all other colour varieties are sapphires.  Therefore, ruby has the same gemmological properties as its sister gem, sapphire.  Pure corundum is colourless with impurities of trace elements causing colour – in the case of ruby, colour is created by trace amounts of chromium and iron with slightly orangey, purplish, brownish or pinkish red caused by relative amounts of these chromophores. Most sources state that ruby should be of medium to medium dark tone with stones of lighter tone being labelled pink or fancy sapphire.

Hardness is 8 meaning it is excellent for use in any type of jewellery requiring no special care.  Enhancement treatments are ubiquitous – like sapphire, unheated rubies are extremely rare and priced at a premium.  Treatment options range from simple heat only to more aggressive treatments such as fracture filling.  For more information on these treatments, see these articles:

• Fracture healing/filling of Mong Hsu Ruby by Richard Hughes
• Glass Filled Star Ruby - AGTA GTC’s Laboratory Update (Sept, 2005)
• Lead Glass Filled Rubies by Vincent Pardieu AIGS (Feb, 2005)
• Pao Mai Rubies by Apsara

Ruby in Australia:  While Australia is a major source of sapphire, ruby is much less common. The major source of gem quality ruby is in the Gloucester-Barrington area, in the drainage of the ancient Barrington volcano. In this area, rubies are found in association with sapphires of various colours. Australian rubies tend to be very small (usually less than a carat) and most deposits are alluvial in nature. Due to the rarity of ruby in Australia, there is limited large-scale mining activity.

The only commercial ruby miner in Australia is Cluff Resources Pacific (an Australian public company)  Cluff has undertaken extensive exploration within the Gloucester area and is currently producing ruby and sapphire from their mine.  Interest in this operation has been relatively high,  perhaps enhanced by the association and original negotiations with the original landowner, the late Kerry Packer,  a very successful entrepreneur well known for his business acumen. These rubies and pink sapphires are now marketed through Ellerston Gems - named for the property where they are mined.   UPDATE:  Cluff is no longer working the Gloucester mine and ruby production has now ceased.

Mythology and Lore:  Ruby is from the Latin word “ruber” or “rubrum” meaning red.  Ruby and sapphire are among the oldest gems known to man, dating back many thousands of years.  They were both held in very high regard, especially the ruby. The ancient Sanskrit name for ruby translate as king of precious stones or leader of precious stones.

Throughout history ruby has been said to preserve health and give invulnerability from wounds, and to guarantee that one’s status and possessions would never be taken. The wearing of a ruby was said to signify manhood, nobility & valour in a man, and pride & passion in a woman. 

Ruby may be given on the 15th and 40th wedding anniversary. It has been said that the ruby’s red glow comes from an internal flame that cannot be extinguished, making a gift of this stone symbolic of everlasting love.  Ruby is also associated with the zodiac sign of Aires. 

Alternatives in Red:  Probably the most well known alternative is red spinel.  In fact, some of the most famous rubies have turned out to be actually spinel.  The 170 carat “Black Prince’s Ruby” on the British Imperial Crown is one of the most famous examples of this.  Far from being a substitute for ruby and sapphire, spinel is now being appreciated for its own special quality and fine specimens are sought after in their own right. 

A cheaper alternative is rubellite tourmaline, which comes in colors from pink to red, sometimes with a violet overtone with a ruby-like rich red being most prized.  For those on a budget, garnet also offers a number of red alternatives. Rhodolite garnet comes in shades from pink to purplish red; almandine garnet is found in violet to pure red; pyrope is produced in yellowish red to dark red; and spessartite garnet is found in brownish orange to brownish red.  Cost for garnet varies greatly depending on which variety is chosen with the rare types relatively more expensive.  Zircon may be a variety of colours including red but the ones found in our mine tend to vary between honey to an orange-red colour.

Links of Interest:

Ruby article by Wikipedia article on Wikipedia
Ruby article by ICGA Gem by Gem article on ICGA Gem by Gem
Ruby article by the Gem Society article on Gem Society
Article on ruby by Geohavens article on Geohavens website

While we do not find rubies in our mine – strictly sapphires only, we have made a few pieces of jewellery featuring rubies as we find these designs always popular.  Feel free to browse our catalogues for any of these items.  This item in the photograph is a lovely set of earrings in 9k yellow gold.  See our website for more choices in jewellery and gemstones.

That’s all for now from Aussie Sapphire

Since starting our blog, we have tried to do a “Gem of the Month” article as each new month comes around.  You can browse through these articles in the relevant category but if you are looking for a particular birthstone that we have covered, see below.

• January – Garnet
• February – Amethyst
• March – Aquamarine and Bloodstone
• April – Diamond
• May – Emerald
• June – Pearl
• July – Ruby
• August – Peridot and Sardonyx
• September – Sapphire and Agate
• October – Opal and Tourmaline
• November – Citrineand Yellow (Precious) Topaz
• December – Blue Topaz

Other gems covered include:  Black Spinel, Watermelon Tourmaline. 

As we go through the months again, we will cover some of the alternative birthstones so keep checking back for new additions.  If you would like us to cover a particular stone, then just drop us a line.  Remember – we have added a page along the top menu bar which gives easy access to all the “Gem of the Month” articles.

The gemstone for May is Emerald, also known as the Gemstone for Spring for its beautiful colour. In fact, relatively clean gems of intense grass-green colour are among the most valuable of all gemstones.

Gemmology Matters: Emerald is the green variety of Beryl – a mineral with the composition Be3Al2(SiO3)6. Emeralds are found in many countries with Columbia recognised as the source of the finest gems – emeralds are also found in Brazil, Pakistan, Russia, Australia, Africa, India, Norway, and the United States.

Emeralds have been commercially mined in Australia in only two main areas: the New England region (Emmaville and Torrington) and in Western Australia near the Poona district. Emeralds were first mined near Emmaville in the early part of the 20th Century with over 53,000 carats produced over 20 years of intermittent production. Another attempt at commercial mining took place at nearby Torrington in the early 1990′s – while the gems were of good quality, it appears the source is now exhausted. The photo at left shows an excellent example of an New England emerald (courtesy GAA – see link below).

The difference between green beryl and true emerald is determined by chemical analysis with emerald containing traces of Chromium Oxide. Where chromium is not present, the colour of green beryl is caused by traces of vanadium and/or iron. There seems to be some discussion among experts about what percentage of chromium compared to vanadium is required to qualify as emerald. Given that gems of a range of colour intensity are found in both Cr-coloured and Va-coloured stones, I suggest the point is somewhat moot and people should choose a colour that appeals to them. In practice, the name emerald is usually reserved for the gems of better colour (intense grass green of pure tone) with those of lighter colour (and perhaps yellowish tone) are referred to as green beryl.

Although emerald has a hardness of 7.5 to 8 on the Moh scale, it is usually regarded as quite a brittle gem due to the high level of inclusions typically found in these stones. Emeralds usually contain many cracks, fissures, and inclusions – for this reason, most emerald are “oiled”, an enhancement treatment which immerses the stone in oil in order to reduce the visibility of the inclusions and improve clarity. Because this treatment is almost universal, it is usually not disclosed to buyers. Emeralds should be treated with particular care and never cleaned in an ultrasonic or steam cleaner as this may damage the stone or may cause the gem to require “re-oiling”.

Synthetic emeralds have been widely available for some decades and will display excellent colour and clarity.  While easily distinguished from natural emeralds with their typically included appearance, microscopic inspection of stones may be necessary to distinguish synthetic emerald from very high quality clean natural emerald.  The example at left is a Chatham emerald (see www.chatham.com for more information).

Mythology and Lore: The name emerald is thought to derive from the Ancient Greek word “smaragdos” meaning green stone and was originally applied to a variety of green colored minerals. Emerald is the birthstone for May as reflected in this old English nursery rhyme:

“Who first beholds the light of day
In spring’s sweet flowery month of May,
And wears a Emerald all her life,
Shall be a loved, and happy wife.”

Emerald is often given as an anniversary gift for the 20th and 35th anniversaries or as an alternate stone for the 55th wedding anniversary. Emerald have been long been associated with eyesight – it has been used to cure diseases of the eye and enhance clairvoyance. It is said that Nero used an eyeglass made of transparent emerald to improve his vision while watching the gladiators in the arena. Emeralds were also used as amulets to ward off epilepsy in children and were thought to improve memory, intelligence, and enhance love and contentment. Legend holds that if an emerald is given by one sweetheart to another, it will pale and grow dull when the love between them fades.

Emeralds have been highly prized by many cultures for thousands of years. Known to have been sold in the ancient market of Babylon over 4000 years ago, they feature in many legends and myths. In Greek mythology, Hermes composed a tablet carved from a giant emerald as a gift for Aphrodite. In the Book of Revelations, the throne of God is said to be made from emerald and the Holy Grail carved from a huge emerald which fell from Satan’s crown upon his banishment from Heaven. In Hebrew lore, emeralds were one of the four precious stones given to Solomon.

Cleopatra prized emeralds above all other gems – the famed emerald mines of Egypt from over 2000 years ago were near the Red Sea and owned by Cleopatra. The Moguls of India, including Shah Jahan, builder of the Taj Mahal, admired emeralds so much they inscribed them with sacred text and wore them as talismans. The incredible beauty and quality of the fine emeralds found in South America enflamed the greed of the Spanish Conquistadors arriving in South America. Pissarro, the leader of the Spanish, ordered that Incan rulers were to be tortured until they revealed the location of the emerald mine. In 1557 the Spanish finally found the fabulous Muzo mine in what is now Colombia – an important source of fine emerald to this day.

Alternatives in Green: Green symbolises the element earth and represents fertility, prosperity, employment, money, healing, and growth. While emerald is perhaps the most valuable of all the green gems, there are alternatives to suit every budget. For everyday wear, green sapphire is an excellent choice with a hardness of 8 – good quality greens are very rare but often priced quite reasonably compared to other sapphire colours. Green sapphire may be less brilliant than some of the other alternatives and can have a slightly olive tone. Demantoid and Tsavorite Garnet are both very bright green gemstones with good brilliance and intense colour. Peridot is an affordable alternative to emerald and in fact is sometimes misleadingly called “Evening Emerald” although usually the colour is slightly yellowish compared to the pure green of quality emerald. Tourmaline can come in beautiful shades of green – often with some blue tone – some varieties are highly sought after. Opaque alternatives in green include jade and chrysoprase.

Links of Interest:

Emerald Factsheet at Mineral Miners
Wikipedia article on Emerald
ICGA Gem-by-Gem article on Emerald
Bernadine Fine Arts Jewelry – Emerald article
GAA Gem Gallery – Australia’s Emerald Deposits
The Emerald Deposits of Muzo, Colombia (reprinted by Palagems)

We currently have a small amount of green beryl in stock – some originates from Nigeria but some is from our own backyard (the Emmaville/Torrington area). Most of this is of the lighter green colour typical of these sources but some very attractive crystals here along with some interesting facet rough.

cheers for now from Andrew and Leah (Aussie Sapphire)