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GEMSTONE EDUCATION

Corundum

Is the name given to two very sought after Gems better known and as Ruby and Sapphire.

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Both these Gemstones are found in various locations around the World, but they are mainly sourced in Countries in Asia, namely Afghanistan, Tanzania, Cambodia, Myanmar (Burma), Mozambique, Siam (Thailand), for Rubies and Sri Lanka, Kashmir, Burma, Madagascar and Australia for Sapphires.

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Both Ruby & Sapphire are from the mineral, Corundum. Rubies are primarily Red and Sapphires are primarily Blue (although you can find green, brown, pink and yellow shades of Sapphire) and the reason they differ in colour depends on the trace element of Chromium, which makes the Ruby red, and is not found in Sapphire.

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VALUE: The value of the Ruby and Sapphire is largely based on its origin and is then dependent on a combination of its colour and the CARAT weight of the Gem (the larger the Gem the higher the price.)

Rubies for Sale London

Ruby

This Gemstone is found in many different shades from pinkish, purplish, and deep red but the most expensive and sought-after quality is the ‘Red’ colour, a vivid red the finest of which is called ‘Pigeons Blood’ colour, a description found on some of the Certificates produced by the Gem Laboratories in our industry.

Burma Ruby

Today, Rubies that originate in Burma are hugely sought after, and are by far the rarest and most expensive Gems that appear on the World market.

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The rich Red colour found in a truly gem quality Burma Ruby is rarely seen in the market today and cannot be replicated by any other Ruby that is found in other locations around the World.

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Burmese Rubies are incredibly scarce, hence the enormous price tag.

Mozambique

Since the mid-nineties Rubies have been discovered and have been increasingly mined in this region.

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One of the areas most commonly associated with Ruby is ‘Montepuez’, situated in the north east of the Country.

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Today, Rubies from Mozambique are being sold worldwide, and tend to be of a deeper darker Red, with a hint of purple or brown, and have become very popular.

Sapphire

The more popular Gem from the Corundum family, the Sapphire is primarily a Blue colour, (many shades from light pale blue through to a deep rich velvety Blue,) although it can also be found in other colours, namely Pink, Yellow, Green and Brown.

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It sells more than Ruby, probably because it is the less expensive of the two Gems, and is mainly sourced in Sri Lanka, Burma and in Madagascar.  The finest quality Sapphire available today is the ‘Kashmir’ sapphire.

Kashmir

Found in the Zanskar range in the Himalayan mountains of Northern India, the sapphire found in this region is hugely sought after although like Burma Rubies, Kashmir Sapphires are rarely seen today and are incredibly expensive.

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The Velvety/Royal blue colour is something rarely seen in Sapphires from other regions.

Sri Lanka

Previously known as Ceylon when the British colonised this Country in 1798.

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Most of the Gem quality blue Sapphire that is found today will originate in Sri Lanka.


These sapphires can be found in many different shades of Blue, Pink and Yellow.

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Sri Lanka is also home to the largest uncut Blue Sapphire found in 2015 and coming in at an astonishing 1404 carats, and valued at $300 million US dollars.

What is meant by heat enhancement
Gems are essentially minerals that are buried deep under the ground.

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If we imagine that the Earth is around four billion years old according to our scientists we must therefore conclude that these minerals have been subjected to the huge radioactive changes that have occurred during the formation of the Earth. It is therefore hardly surprising that these minerals have lost much of the natural colour and beauty that they originally had.

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Many hundreds of years ago miners and traders discovered through knowledge gleaned over time that if the Corundum Gems were subjected to heat, at a relatively low temperature, the colour in the Gem crystals were brought back to life and their original Blue or Red colour that became indicative of the Ruby and Sapphire, returned.

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This original heating technique is a completely accepted practice that takes place although it must be stated that in the past decade other enhancements have been found and are subject to non-acceptance within our industry.

Non-enhancement (Natural Gems)
Although many of the Rubies and Sapphires we see today have been subjected to heat enhancement a small amount of the production that is mined comes out of the ground in its original colour, as it was created so to speak, and this type of Gem is referred to as Non-Enhanced, Natural or Unheated.

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Such Gems are small in quantity and are considerably more expensive than heated pieces when being purchased in the World market.

Gem Laboratories
These scientists give the trade an independent ‘opinion’ on the enhancements or non-enhancements that are part and parcel of the Gemstones you will buy and they have become an essential part of our industry.

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Among the most highly regarded Gemstone Laboratories in our industry are the GRS, Gubelin, SSEF or C.Dunaigre (Swiss) Laboratories and the AGL and GIA Laboratories situated in New York City.

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We certificate most of our stock through these renowned and approved laboratories.

Gemstone Experts London

How can we help?

Sico International are experts in sourcing and buying the finest and rarest Rubies available anywhere in the world. Contact us and we'll be delighted to give you advice in helping you choose the right Rubies, Sapphires or Diamonds.

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