Like any other gemstone, the cost of a ruby can vary depending on the quality and carat weight. Note that carat weight is the unit of measurement that most gemstones are weighted by (1 carat = 0.2 grams). Rubies can run as little as $1 a carat to $100,000+ a carat, depending on the 4Cs. One of the most expensive rubies ever sold is the Sunrise Ruby, selling for over a million dollars a carat at 25 carats.
The 4Cs and Their Considerations
| Color | Clarity inclusions | Cut | Carat Weight |
| Hue Tone Saturation | Location Type Size Number Transparency Contrast with Ruby | Brilliance Symmetry Lack of windowing Lack of extinction Quality of Polish | Rarity of carat weight (larger rubies are exponentially rarer) |
What dictates the price is the quality of the gem and its color, clarity, cut, and carat weight, though other factors can further determine ruby pricing like treatments, international customs, and overall rarity of desirable features. Despite all the considerations though, the one factor that is prized above all else is the color. This single factor is the main drive to an entire industry.
In rubies this is a little limited since the only color they can be is primarily red, with a medium to dark tone, though colors modifying the red are permissible.
Red
U12034 | “U12034”
Orangish Red
U6671 | “U6671”
Purplish Red
R4704 | “R4704”
Pinkish Red
R7699 | “R7699”
There is no such thing as a light ruby, only pink sapphires. Despite being the same material, there is a significant price difference between corundum labelled as “pink sapphire” versus “ruby” with ruby material commanding higher prices. However, the exact colors that barely qualify as pink or red in corundum is an ongoing debate.
Baseline Pricing
Based on what is available in our inventory, the vast majority of rubies that weigh around 1 carat are at least $1,000 per carat. This amount easily doubles if the ruby has not been heat-treated and will increase steeply for rubies that show good color, even if they have been heated. When dealing with rubies that are a few carats or more, the price increases exponentially even if the color is not ideal. This is due to the rarity of a higher carat weight.
While the idea that the bigger the gemstone, the rarer it is holds true for any gem to varying degrees, it is especially true for rubies. Gem-quality blue sapphires can grow to monstrous sizes of more than 100 carats, but gem-quality rubies do not reach these sizes. This is because their coloring agent, chromium, doesn’t mix with the corundum as well as the agents for blue sapphires (iron and titanium) do. The rarity created by that factor alone makes the price of rubies dwarf that of any equal-sized sapphire in larger carat weights.
B7139 | medium | “B7139 – 7.04 Carats – $4,125 per carat Total: $29,040”
R10788 | medium | “R10788 – 7.01 Carats – $25,200 percarat Total: $176,652”
Even at smaller sizes; rubies are usually more expensive, though the price gap is not as bad with the larger items.
R11744 | medium
Ruby ID: R11744 – Carat Weight: 1.06 – Origin: Mozambique –Treatment: None
Per Carat Price: $9,775.00
Total: $10,361.50
R11744 is ideally colored, has an excellent cut, is very clear, and, as noted above, it has not been treated. While being clear is more common in Mozambique rubies than Burmese rubies, it still commands phenomenal prices.
R11949 | medium
Ruby ID: R11949 – Carat Weight: 1.11 – Origin: Myanmar (formerly Burma) – Treatment: Heated
Per Carat Price: $3,885.00
Total: $4,312.35
Weighing roughly the same as the ruby above, R11949 is less than half the price entirely because of the fact it has been heat-treated. Heat-treatments are a very common treatment for rubies to improve clarity and color. Treated gems give vendors more rubies to sell, and a better price for buyers.
R11966 | medium
Ruby ID: R11966 – Carat Weight: 0.8 – Origin: Myanmar (formerly Burma) – Treatment: Heated
Per Carat Price: $1,530.00
Total: $1,224.00
There are three factors that make this ruby’s price. Most importantly, the color is heavily modified by pink. In addition, this ruby has been heat-treated. Lastly the weight is less than a carat. Gem prices increase at various carat weights like 1ct, 2ct, 3ct, etc, so falling under 1ct reduces price further.
R12398 | medium
Ruby ID: R12398 – Carat Weight: 0.91 – Origin: Myanmar (formerly Burma) – Treatment: Heated
Per Carat Price: $3,150.00
Total: $2,866.50
Not only is the per carat price lower for R12398 than the first two rubies, the dip under 1ct further reduces it. The color is not quite as nice either, along with lower clarity than the other gems above. Like most rubies it has been treated too. However, the red is not modified and keeps the price higher than R11966.
No matter what choice is made, rubies are frequently the most expensive colored stone on the market. However, for the same carat weight a treated ruby with a slight color modifier will be less than 20% of an untreated ruby that is a perfect red. The price gap between all these different rubies is significant too, with many high-quality sapphires and emeralds able to command similar or higher prices than a lot of rubies.
With our knowledge of all these factors, the Natural Ruby Company is designed to help find the perfect ruby across the 4Cs.
