All gemstones are categorised into mineral species based on their chemical composition. Rubies belong to the mineral species known as Corundum, which, in its purest form is actually colourless! Chromium, a trace element, gives the ruby its red colour, varying in shades of orangy-red to deep, pinkish-red and plum. 

Measuring at 9 on the Mohs scale of hardness, rubies are relatively hard and tough, a great choice for daily jewellery. (For reference, diamonds measure at 10 on the Mohs scale.) 

Rubies are formed under the earth's surface, hosted in metamorphic rocks such as marble or igneous rocks like basalt rock. Marbles' low iron content results in an intense red colour in the rubies, making them more desirable and valuable. 

The quality of a ruby is based on the 4 C’s, Cut, Colour, Clarity, and Carat weight, similar to diamonds, but with different requirements. 

Rubies can command the highest per-carat price of any coloured stone! We have put together this sheet to help explain everything you need to consider when purchasing a Ruby. 

All gemstones are graded using the combination of these characteristics to assess their value and are priced at the US dollar rate of the day. This means that our quotations are time-sensitive and subject to change.

 

This category refers firstly to the shape of the ruby i.e. Round, Oval, Pear, Princess, Marquise, Emerald, Radiant, etc. 

This is purely dependent on personal preference and design aesthetic! Secondly, the cut grade of a ruby refers to how well it has been cut and depends on things like symmetry and proportions, as well as the quality of faceting and polish. 

For us, this is perhaps the most important thing to consider when looking at gemstones to buy, as you want one that delivers a maximum return of colour & light. 

Here, we also look at how the cut enhances the ruby’s hue, tone, and saturation. Ruby crystals have pleochroic characteristics - the appearance of different colours in different crystal directions.

This plays a vital role when cutting the stone. A well-cut ruby has minimal orangy-red hues and the desirable highlighted grape red shades - therefore, increasing its value.

A top-quality ruby with a poor Cut Grade could have emphasized orangy-red colours which would decrease the value of the stone, even though it might have a high carat weight.

We only consider rubies with Very Good and Good Cut Grade for our clients, to ensure you are getting the best quality. 

 

 

 

Clarity

Gemstones are formed far beneath the earth’s surface and when exposed to tremendous pressure and heat, a variety of internal characteristics called "inclusions" and external characteristics occur. 

Inclusions can consist of tiny crystals that are trapped while the stone is formed or irregularities in the atomic structure. 

The clarity grade of a ruby refers to the presence and visibility of inclusions in the stone. Top quality rubies without inclusions are more desirable and extremely rare.    Obvious fissures or inclusions that reduce transparency or brightness lower a ruby’s value dramatically as this results in a more dull red colour. 

Significant surface-reaching fractures can pose durability threats and lower the price of the ruby. Some inclusions actually contribute positively to a ruby’s appearance. 

The presence of rutile silk causes light to scatter across facets that might otherwise be too dark. This adds softness to the colour and spreads the colour more evenly across the ruby’s crown. The same applies to needle inclusions that intersect and cause the star effect, called asterism, when the stone is cut with a curved upper surface, called a cabochon cut. 

Below are images of the most common inclusions found in rubies: 

 

Colour

The colour grade of a ruby refers to the presence of colour in the gemstone. The strength of a ruby’s red depends on how much chromium is present—the more chromium, the stronger the red colour. Chromium can also cause fluorescence, which adds to the intensity of the red colour. 

The finest ruby has a pure, vibrant red to slightly purplish grape red colour. The pure red colours with vivid colour saturation command the highest prices and rubies with overtones of orange and purple are less costly.

If the colour is too dark, it affects the stone’s brightness negatively. At the other extreme, if the colour is too light, the stone may be considered to be a pink sapphire, even if colour strength or intensity is high.

Historically, the term “pigeon’s blood” described the red to slightly purple colour of rubies with a soft, glowing, red fluorescence.

The most vital aspect when choosing a gemstone is choosing the one that appeals to you the most, and depends largely on personal preference. 

 

 

 

Carat

Carat weight refers to the size of a stone. 

The value of a ruby increases with its carat weight, as it gets bigger (and heavier).

Fine-quality rubies that weigh over one carat are very rare, but commercial-quality rubies which may be slightly included are commonly available in a wide range of sizes. The price per carat for a fine quality ruby goes up significantly as it increases in size.  

However, it is worth noting that a high-quality ruby with a lower carat weight can hold more value than a big ruby with a higher carat weight but lower quality due to factors like cut or colour. 

 

Bonus 'C' - Characteristic

The Four C’s are the most traditional guide for determining a gemstone's quality. These measures will always hold value. 

We believe in each stone having an appeal that is not necessarily included in the four C’s, and this is why it is very important to view a few options before purchasing. 

We are focused on finding the right ruby, for YOU. 

 

Upcycling

We love working with family jewels and heirlooms. Creating new pieces containing old stones is our forte! We happily accept gemstones brought in by clients for their own pieces.

We will, however, always test the stones brought into our studio before accepting them, to determine whether they are genuine.

 

Caring for your Rubies

Even though rubies are nearly as hard as diamonds, they are not indestructible. It is a tricky concept to wrap your head around, but they can crack or chip due to blunt force or a hard blow (especially heavily included rubies). 

Therefore, we always recommend that you take extra special care of your ruby jewellery to ensure its signature sparkle.

- Avoid exposure to any harsh chemicals 

- Avoid wearing your jewels while swimming, hiking, washing dishes, gyming , or any activities where they are at risk of being knocked or scratched. 

- Always clean your pieces with warm soapy water and a soft toothbrush. For any specific cleaning measures, we will make recommendations or ask you to visit the studio. 

- Store your pieces somewhere SECURE, in its box, apart from other jewels which may cut or scratch them. 

- Bring your piece to the studio once a year for us to give it a proper professional clean and inspect it for any traumas or weakness in the settings.

Below are some examples of Ruby pieces we have made in our studio: