What is an untreated unheated sapphire?

Beauty, rarity and durability are the three factors that make a gemstone valuable and why we fall in love with them. 

Untreated sapphires means those that have not had any form of treatment to enhance their colour or clarity. This means these sapphires are in their purest form; they were mined and simply cut and polished to show their inner beauty. Most of the time untreated sapphires are referred to as unheated sapphires as the heat treatment need to be applied in order to perform any other enhancement. Unheated sapphires and untreated sapphires are one and the same as no treatment can be applied to a sapphire without the help of heat treatment. Unheated sapphires mean the sapphire is natural and it has not been enhanced by any form of heat treatment or any other treatment.  

Why choose an untreated unheated sapphire? 

Rarity of a gemstone
It is not just the beauty that makes us want to own something valuable. 
We all want something that is uncommon and scarce. Jewellery is also a symbol of wealth. Otherwise you would be wearing something you can buy from the corner shop but beautiful - not that there is anything wrong with it but it is not the purpose of having a valuable piece of jewellery.

Unless we learn, we are unaware that majority of the gemstones in the market are treated in some manner. It is important to be informed of choices available to you. 

Treatments: rarity and durability. 

Heat Treatment of Sapphires
Treatments include heat treatment to alter colour of a sapphire or to improve its clarity. Heat treatment is a permanent treatment when it comes to sapphires and the gemstone will look exactly the same in years to come. Durability of the sapphire will not change due to heat treatment.

How does heat treatment change sapphires
Heat treatment may enhance the existing colour of the sapphire by melting silk type inclusions to enrich the body colour and/or by removing secondary colours visible in natural sapphires. 

These are known as heated sapphires or treated sapphires. Particular colours such as royal blue is near impossible to find in nature without heat treatment. This colour was first made famous by Princess Diana’s engagement ring and created a huge demand to replicate it. Therefore these particular colours even in heated sapphires can command a reasonably high value, however an equivalent untreated natural sapphire would be more than the price of a similar heat treated sapphire. 

Sapphire Heat Treatment

Image via Lotus Gemmology 

Other types of sapphire treatments
There are also chemical treatments such as diffusion treatment and surface coating where colour is penetrated into the gem crystal or a layer of synthetic sapphire is deposited on to a lower quality natural sapphire. Other treatments include doublets where a layer of sapphire is glued on a to piece of synthetic sapphire or on to another type of gemstone. These type of treated sapphires are abundant and has a fraction of the value of an untreated sapphires. Diffusion treatment can be difficult to detect beyond heat treatment. 

Durability of treated sapphires
Heat treatment alone does not affect the durability of sapphires. 
It is important to be aware that fracture filled or doublet sapphires can be problematic in future as they are less durable.

Why are sapphires treated  
It is important to recognise the necessity of such treatment; for example not everyone can afford a natural gemstone and they still want to be able to wear something beautiful even for a shorter time. It also reduces the wastage of some poor quality gemstones that has already gone through the mining process. It is important to reduce wasted in all aspects of our lives including in gemstones. While at Deliqa Gems we do not carry such sapphires or gemstones, by no means we discourage anyone from purchasing such treated gemstones as long as you are fully informed of affects on durability and price due to such treatments. 

What is offered at Deliqa Gems
We find it phenomenal how a natural untreated sapphire has survived weathering over thousands of years, be unearthed in magical colours and still be clean with so much sparkle. Such survival is phenomenal.

To maintain the integrity of what we offer, at Deliqa Gems we carry a selection of permanent heat treated sapphires though majority of our collection is unheated sapphires. We do not carry sapphires treated with other types of treatments that may become problematic in future.  

What is important is to recognise the value difference; what you want to wear and how you feel about wearing it. Are you looking for something just beautiful or something that is beautiful as well as exceptional?

2.6 carat unheated cushion shape Ceylon cornflower blue sapphire


2 carat permanent heat treated pear shape royal blue sapphire

Just to sum it up in a measurable number, on average 95% of the sapphires available in the market today have been through some form of treatment (source: GIA) and only 5% are unheated natural sapphires. At Deliqa Gems we have chosen to offer the cream of the crop to our valuable clients. What is available at Deliqa Gems are some of the finest sapphires nature has to offer. 

Sasha Gammampila
Gemmologist