What is a Sapphire?

For those curious as to the science and the gemmology of sapphire this article is a great guide.


What is in it?


Sapphire is a gemstone that is mainly composed of corundum along with; iron, titanium, chromium and copper. All of which are minerals. If you see sapphire that is of a blue, yellow, purple, orange or even a greenish colour, minerals such as iron, titanium, chromium copper and/or magnesium give the corundum that colour.


What is Corundum?


Corundum is a crystalline[1] form of aluminium oxide. The crystalline has traces of other minerals such as iron, titanium and chromium[2]. In its most natural state, the mineral is transparent. This does not remain true because the corundum can actually shift colours when tainted. The transparent minerals are used as gems and are called ruby if they give a red glow and padparadscha[3] if given a colour of pink-orange. All other corundum that projects any other colour are labelled as sapphire.

There are two dominant ways in which corundum is formed. One is the metamorphosis[4] of limestone and the other involves the igneous occurrence in rocks lacking silica[5].

Corundum is rated as a 9.0 out of ten in terms of the Mohs scale of mineral hardness.


What is Aluminium Oxide?


Aluminium Oxide consists of the compounds oxygen and aluminium (Al2O3). Alpha-Al2O3 or corundum is the most commonly known and significant modifications of aluminium oxide.

Aluminium oxide is produced by machine from the mineral bauxite. There are currently 20 billion tons of bauxite deposits in the world. Aluminium and aluminium oxide are manufactured by the principles of the Bayer method: Bauxite[6] is broken and dried and is then dissolved using concentrated sodium hydroxide soloution. The left overs (iron, silicon and titanium) are segregated from the bauxite in the red mud. The aluminium hydroxide is then precipitated from the mix and then calcinated[7] at 200-1300°C to form Al2O3.


How are Sapphires Cut?


Sapphires are very rare gems. You will often see sapphire presented as jewellery in the shape of either an oval or a cushion. Ovals and cushion tend to preserve most of the original rough. Round sapphires are popular as well, however their final shape involves removing a large portion of rough and are as a result are costlier than ovals and cushions.

Sapphires are treated by several methods so that the quality of the gem and colour are enhanced. One technique of doing this is by heating. This type of treatment is done in furnaces between 500-1800 degrees Celsius for hours at a time. By heating the sapphire, the colour of the gem becomes more blue. As well the stone becomes more clear because it loses silk and it becomes clearer under magnification. This is just one of other techniques used to treat sapphire.


Where is Sapphire Mined?


Sapphires are found in igneous[8] and metamorphic rocks. When sapphires are extracted from solid host rock they are labelled as primary deposits. They are considered as secondary deposits when they are found some distance from their original source. Rocks are hit against by water and wind. The process of erosion moves small pieces of rocks into streams of water where they are broken, releasing any gems that they contain.


Word Search


www.dictionary.com

[1] Pertaining to crystals or their formation.

[2] A lustrous, hard, brittle, metallic element used in alloy steels for hardness and corrosion resistance.

[3] A delicate light to medium toned pink-orange to orange-pink hue corundum.

[4] Any complete change in appearance, character, circumstances, etc.

[5] The dioxide form of silicon.

[6] An amorphous clayey rock that is the chief commercial ore of aluminum.

[7] To convert into calx (the oxide or ashy substance that remains after metals, minerals, etc., have been thoroughly roasted or burned) by heating or burning.

[8] Geology . produced under conditions involving intense heat, as rocks of volcanic origin or rocks crystallized from molten magma.

 


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Why You Should Invest in Gold

Even though gold is down in today’s current market value, it is still the most popular investment among precious metals. Sure many might say that gold is a risky investment, that the price of gold keeps on fluctuating and the value of it is near unpredictable. That is because gold is not a short-term investment, it is a long term investment. This may sound obvious, but gold is becoming more scarce. Despite what experts say to not invest in gold, the return of it over time is rewarding. From 1970 to 2010, the price of gold rose from 37 USD/ozt to 1410 USD/ozt or otherwise a 3790% net change.

You better buy some gold before it becomes too expensive or too little of it left. World renowned investor Warren Buffet has claimed that the total amount of gold in the world that is above-ground, could fit into a cube with sides of just 20 meters (66 ft), most of which is contained in jewellery. To put it into a more visual example, the amount of above-ground gold in the world would be able to fill up an entire NFL football stadium to a depth of about five feet.

If there is one thing that you should get out of this article it is that:

a) gold will become rarer as time goes on

b)gold is a long term investment

c) gold will increase in value in the long term.

For those who are looking at investing in gold they should do it soon as gold is at a cheaper price. Right now the value of gold is down 23% in USD.