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Gemstone for a 5th anniversary: sapphire

TELL YOUR FRIENDS....

Congratulations to all of you celebrating a 5th anniversary, the anniversary of sapphire!  Symbolising love and fidelity, sapphire is a beautiful gemstone that’s tough enough to withstand a few knocks – just like a good marriage.

5th anniversary gemstone | www.gemstonedetective.com

Though blue is the most popular and well-known colour, sapphires occur in a wide range of pretty hues: blue, pink, green, yellow, orange, purple, black and even colourless.  There’s no such thing as a red sapphire though.  Know why?  It’s because a red sapphire is known as a ruby.  Sapphire and ruby are both varieties of the mineral corundum, and the variation in colour is caused by different chemical elements within the gemstones’ structure. 

I’ve come across some phenomenal sapphires on my travels, and I don’t just mean that they made my jaw drop!  The term ‘phenomenal’ in gemmology refers to gemstones that have fascinating optical properties. 

The most well-known type of phenomenal sapphire is probably the star sapphire.  Star sapphires exhibit a property called ‘astersim’, which means that they seem to have a star shape floating across their surface.  Asterism happens when light bounces off dense, linear inclusions of titanium dioxide (also known as ‘rutile’ or ‘silk’) in the gemstone’s body.   In black star sapphires, the rutile is hematite and some Thai sapphires contain both titanium dioxide and hematite.  As well as causing the floating star effect, the rutile gives the star sapphire its milky, opaque appearance.  Depending on the nature of the rutile, a sapphire may exhibit a four, six or twelve-rayed star.

You probably know that alexandrite is a colour change gemstone, but did you know that it’s possible to buy a colour change sapphire?  Colour change gemstones appear to be different colours in natural and artificial light because the gemstone’s chemical makeup means that particular ranges of wavelength (i.e. colours) in the light spectrum are absorbed more intensely under one light source than another.  The colour change in sapphires is most commonly a subtle but pretty change from blue to violet. 

Bi-coloured or ‘parti’ sapphire displays two different colours (usually blue and greenish yellow) within the gemstone no matter what the light source.  Though found in Tanzania, Madagascar and Nigeria, the world’s main source of parti sapphire is Australia.  I was lucky enough to find a few myself, when fossicking in the outback on my travels down under.  These intriguing and unusual sapphires certainly make for a striking piece of jewellery!

Happy 5th anniversary! Let’s not forget that sapphire is also September’s birthstone!

Kim Rix GG, GIA

Gemstone Detective

Be sure. Be smart. Buy with confidence

3rd anniversary gemstone: pearl

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Gemstone for a 3rd Anniversary: Pearl

Jackie Kennedy once said, “Pearls are always appropriate,”  but this is particularly true if you’re celebrating a 3rd anniversary. 

Pearls are what we call organic gemstones: gemstones that are produced by a living organism.  Pearls are formed inside molluscs such as oysters, clams and mussels, and occur when a small piece of grit or sand becomes lodged within the mollusc’s soft insides.  To protect itself, the mollusc secretes a substance called nacre, which hardens in thousands of layers around the object.  The result?  A beautiful iridescent pearl.   

Like most gemstones, pearls vary hugely in price and several factors determine how much you will pay for yours.  Pearls which occur without human intervention are called ‘natural pearls’, and a necklace of them would set you back vast amounts of cash.  Why?  It could well mean looking through 100,000 oysters to find enough pearls of the right size and colour to string a necklace!  Farmed pearls on the other hand, are formed around small ‘seed’ beads deliberately placed into the mollusc.

If you don’t have much to spend on your 3rd anniversary gemstone, go for freshwater pearls.  These are the most affordable way to own pearls.  They’re often sold as irregular shaped beads called baroque pearls. 

More expensive, though still within the bounds of reasonable, are farmed Akoya pearls.  With a diameter of between 4 and 10mm, these pearls are grown off the coast of Japan and are what we think of when we imagine the classic strand of round white pearls.

If you’re after somethinga little unusual, you could go for Tahitian pearls.  These French Polynesian beauties are large—up to 15mm in diameter—and naturally dark in colour, thanks to the nacre secreted by the native ‘black-lipped’ oyster.  Though they are also referred to as ‘black pearls’, most range in colour from dark grey and dark green to silver.  It’s rare to find perfectly round Tahitian pearls, but even the baroque shapes are expensive.

Looking to splash some serious cash on your 3rd anniversary gemstone?  South Sea pearls can fetch tens of thousands of dollars per pearl.  These stunning specimens sometimes exceed 20mm and form in various hues of cream, white and gold..

As well as being the gemstone for your 3rd anniversary, pearl is also the gemstone for your 30th anniversary.  Perhaps you could commission a piece of pearl jewellery for your 3rd anniversary that will eventually be joined by another for your 30th!

Be well. Take care!

Kim Rix GG GIA

Gemstone Detective

Be sure. Be smart. Buy with confidence