March 18, 2020

Sapphire gemstones

At Blackacre we adore sapphires, they have superb qualities and naturally are found in an abundance of colours.

Sapphires are part of the mineral family corundum, this family also includes ruby. Ruby is only the red variety of corundum and sapphire is everything else. On the mohs scale of hardness, sapphire comes in at a 7.5-8, making it a tough stone and therefore durable and highly suited for jewellery.

Sapphires are found in a variety of places such as, Sri Lanka (formerly Ceylon), Thailand, Australia, Madagascar, Vietnam, Cambodia, and the USA. The most exquisite “royal blue” sapphires are found in Myanmar (Formerly Burma) and Kashmir, these are highly sought-after and treasured by many.

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Sri Lankan Countryside

When looking to buy sapphires, many are confused by the terms “Natural” and “Treated”. A natural gemstone is one which has been taken straight out of the ground, cut and then sent to market. A treated gem is that which has been subjected to some form of clarity or colour enhancement, usually heat treatment, this by no means classifies them as synthetic gemstones. By heating sapphires, a weaker colour gem with visible “silk” (inclusions within the gem), becomes a much more vibrant tone with a better clarity. This technique is often used and is widely accepted in the gem trade. Sapphires often have small inclusions when looked at with a jewellers loupe, the fewer inclusions there are, the greater increase in price.

Blue Sapphires

The most popular colour of sapphire, blues have been prized by royals and mere-mortals alike. The colour can vary from grey blue, pale blue, cornflower blue, royal blue, to deep blue-black. Mid-blue to rich royal blue tones are the most favoured of this colour of sapphire.

Padparadscha Sapphires

Meaning “Lotus Blossom” in Sanskrit, Padparadscha sapphires are a signature mixture of orange and pink which are extremely rare and highly collectable. It is debated what colour a Padparadscha sapphire should be, whether Salmon or Sunrise, however it is generally accepted that a light to medium pinkish-orange or orangey-pink is the correct tone.

Colour Change Sapphires

Sometimes known as Chameleon sapphires, this variety of corundum changes colour under different lights. Under daylight (fluorescent or LED daylight lamp), the stone will appear bluish-violet, whereas under incandescent lamps it will appear strong violetish purple to strong reddish purple. The colour change can be graded as light, medium or dark.

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