What to remember
Cost and carat
The final price of your ruby will be determined by many factors, including colour, carat, cut, clarity, treatment and origin. The right combination of these will ensure your gem’s long-term value remains steady and perhaps even increases over time.
Large rubies are extremely rare and in limited supply. For this reason, carat weight will make the price of your gem increase exponentially. The price of a 10-carat ruby is usually 100 times that of a one-carat stone.
Colour is the most significant factor when it comes to valuing a ruby. Unlike diamonds, there is no internationally accepted colour grading system for this gemstone. 77 Diamonds have adopted the ICL’s seven levels of colour intensity, which range from Dark to Medium Intense.
Rubies that are a shade above Medium Intense are called pink sapphires, as both these gemstones are part of the same mineral variety, corundum.
The most sought-after colour in rubies is Vivid. Referred to as ‘pigeon blood’ in the trade, this colour seems to have an almost fluorescent quality, lending intense fire to your jewellery.Our rubies are classified in four different shades: pure, purplish, orangey and pinkish red. The intense saturation of pure red rubies make them significantly more expensive. If your ruby has strong orange, purple and pink overtones, this will affect long-term value.
Unlike diamonds, inclusions in rubies are common, well-accepted and often serve to indicate the origin of the stone. There are three levels of clarity:
Cut and shape
- “Eye Clean” (EC1 – EC2) indicates that inclusions are invisible to the unaided eye.
- “Visible inclusions” (VI1 – VI2) indicates that inclusions are only slightly visible to the unaided eye.
- “Included” (I1 – I2) indicates that inclusions are obvious to the unaided eye.
Usually, rubies are both brilliant and step cut.
A brilliant cut ensures an even display of light reflections throughout the gem, while a step cut lends intense fire to the piece. Some rubies may also be cabochon cut, giving them a smooth and rounded finish. Keep in mind, the quality of the cut will determine the overall price of your gemstone.
On the other hand, the shape of your ruby will not have a direct impact on price, as this is largely a matter of personal preference. The most common shapes for rubies are round and oval
, but you may also find marquise or pear
shaped stones. Treatment
Rubies are most commonly enhanced through heat treatment
. By applying heat to the gem, experts have found that both colour and clarity are greatly intensified. The first examples of heat-treated rubies date as far back as the Roman Empire. This is a widely accepted practice in the jewellery trade and most methods have no harmful effect on the stone’s longevity.
At 77 diamonds, we provide two forms of ruby treatment: heated (H) and heated with flux (Hf)
. These treatments are stable, permanent and do not require any special care. We do not sell rubies treated with Beryllium or lead-glass, as these methods significantly weaken the gem.
Only the finest and rarest rubies are unearthed in a perfect state without any need for further treatment, making them significantly more valuable. Origin
Although some rubies may look similar, their prices will differ due to origin. The most expensive rubies come from Myanmar
(also known as Burma), where rubies have been mined for thousands of years. The second finest origin is considered to be Mozambique and Thailand
, followed closely by Tanzania and Madagascar.
Finally, rubies from areas such as Vietnam
are considered to be of lower value.