The September birthstone is sapphire, which is a gem-quality variety of the mineral corundum. Sapphires come in a range of blue shades, from light to dark, as well as other colors like pink, yellow, and green. The most prized and valuable sapphires are a medium to medium dark blue. Let’s take a closer look at sapphire colors and what makes blue sapphires in September birthstones so special.
What is Sapphire
Sapphire is a crystalline form of the mineral corundum, which consists of aluminum oxide. Trace elements like iron, titanium, chromium, copper, and magnesium give corundum its wide range of colors. The red variety is known as ruby, while all other gem-quality corundum is classified as sapphire.
Blue sapphires get their color mainly from iron and titanium impurities. The more iron present, the deeper and richer the blue color. Sapphires with just trace amounts of iron show lighter blue shades. Titanium produces a vivid pure blue. The most prized blues are a blend of both iron and titanium.
Sapphire Color Range
Sapphires come in every color but red. Blue is the most common and popular, but sapphires also occur naturally in shades of pink, purple, orange, yellow, green and white. Some rarer fancy sapphires are multicolored, with a blend of hues in patterns like color zoning, stars, and cat’s eyes.
Here are the main color varieties of sapphire, from light to dark:
- Cornflower blue – Very light blue with a hint of gray
- Sky blue – Soft light blue
- Royal blue – Classic medium blue
- Indigo – Deeper blue with a violet tone
- Navy – Very dark blue, almost black
Pink sapphires range from light pink to vivid pink to reddish pink. Yellow sapphires are typically a lemon yellow color. Green sapphires also vary from light mint green to deeper emerald green shades. White sapphires are actually colorless and exhibit a brilliant white sheen.
Most Valuable Blue Sapphire Shades
In the sapphire trade, some shades of blue are more prized than others. Here are the top blue sapphire color preferences:
| Blue Sapphire Color | Popularity |
|---|---|
| Royal Blue | Most popular |
| Cornflower Blue | Less desirable |
| Sky Blue | Lower value |
| Indigo | Rarer |
| Navy | Too dark |
Royal blue is the classic sapphire shade most consumers look for. It has a rich medium blue tone that is bright and vivid but not too light or too dark. Sky blue and cornflower blue sapphires tend to be cheaper since they are so light. Navy blue is so dark it loses the brilliance that makes sapphire special. Indigo falls somewhere in between – rarer but not always as valued as the perfect royal blue.
What Makes Sapphire Blue
The trace minerals iron and titanium are responsible for sapphire’s range of blues. Here’s how they influence color:
- Iron – Produces deeper blue hues, from royal blue to navy
- Titanium – Creates bright vivid blues like cornflower and sky blue
The most expensive sapphires have just the right combination of both iron and titanium to display an intense medium blue with high saturation. Too much iron makes the stone dark. Too much titanium gives a pale washed out blue. With balanced levels, the colors enhance each other.
Other Factors Affecting Color
In addition to trace elements, these other factors influence the depth and intensity of blue:
- Clarity – Clean stones allow full saturation of color. Inclusions dilute the blue.
- Cut – Well-cut sapphires maximize color saturation. Poor cuts decrease the vividness of the hue.
- Source – Where the stone is mined affects the trace elements and thus the shade of blue.
The most brilliant blue sapphires have high clarity, excellent cut, and come from renowned sources like Sri Lanka, Myanmar, and Kashmir. The combination of ideal traits allows the best color to shine through.
Matching Sapphire Color
When selecting a sapphire, it’s important to pay attention to factors beyond just the hue. Here’s what to look for to get an ideal blue shade:
- Medium to medium dark blue
- Balanced iron and titanium content
- High clarity and quality cut
- Certified source origin
Be sure to compare stones in similar lighting conditions. Incandescent bulbs enhance blue more than bright sunlight. Set against white, blue will appear more pronounced. The setting metal can also influence color appearance, with warm metals like yellow gold intensifying blue more than cool metals like white gold and platinum.
How Blue Sapphires Are Graded
Gemologists grade the color quality of blue sapphires based on three main criteria:
- Hue – The shade of blue, from light to dark
- Tone – How light or dark the color is
- Saturation – Intensity and vividness of the blue color
Hue refers specifically to the spectral color, like cornflower or navy. Tone measures the lightness or darkness of the hue. Saturation indicates how pure, rich, and brilliant the hue is. Sapphires with strong saturation are highly desired.
These three factors are considered on a grading scale to determine the overall color grade. Here is a typical blue sapphire color grading scale:
| Color Grade | Description |
|---|---|
| AAA | Vivid medium blue |
| AA | Moderately strong blue |
| A | Slightly grayish blue |
| B | Noticeable gray-blue |
| C | Dark inky blue |
The highest grade AAA sapphires feature a perfect balance of iron and titanium content to deliver vivid medium blue hues with strong saturation when viewed face up. Lower grades exhibit less ideal colors that are too light, too dark, or more muted and grayish.
Most Valued Blue Sapphire Shades
Taking into account popularity, rarity, and grading, these blue sapphire shades are the most valued for September birthstone jewelry:
- Rich royal blue
- Vibrant cornflower blue
- Saturated medium blue
Stones in these hues command higher prices because they exhibit attributes like:
- Balanced iron and titanium content
- Medium to medium dark tone
- Brilliant saturation
- High clarity
- Ideal cut proportions
Lighter blues can look gorgeous in sapphires but don’t offer quite the same brilliance and fire. Darker shades lose the scintillating liveliness that makes fine sapphire so captivating.
Ideal Blue Sapphires for Jewelry
When choosing a September birthstone sapphire for jewelry, look for stones in these ideal blue color ranges:
| Jewelry Type | Best Blue Hues |
|---|---|
| Solitaire rings | Royal to medium blue |
| Pendants | Royal to vivid blue |
| Earrings | Sky to royal blue |
| Bracelets | Medium to cornflower blue |
Lighter blues like sky blue work well in earrings and bracelets where the stones are set in clusters and have movement. The bolder medium royal blue hues are ideal for solitaire rings. Vivid cornflower blue pendants make a dazzling statement. Matching the setting metal can also enhance the blue – yellow gold pairs nicely with all shades.
Most Popular Sapphire Colors
Blue is the overwhelmingly preferred sapphire color, accounting for over 85% of the market. But other shades have their admirers as well. Here are the 5 most popular sapphire colors:
- Blue
- Pink
- Yellow
- White
- Padparadscha (orange-pink)
While blue sapphires are considered traditional, some consumers opt for other colors to have something more unique. Vivid hot pink sapphires are trendy in modern jewelry designs. Padparadscha sapphires combine the best of both worlds, with a beautiful orange and pink color blend.
September Birthstones by Zodiac
In addition to sapphire, zodiac signs associated with September may have additional birthstones:
| Zodiac Sign | Birthstones |
|---|---|
| Virgo | Sapphire, peridot |
| Libra | Sapphire, opal |
Virgos can also claim peridot as their birthstone, with its bright green hue symbolizing growth and renewal. For Libras, the additional birthstone opal represents hope, innocence and purity with its shimmering rainbow colors.
Most Valuable Sapphire Sources
The geographical source of sapphires plays a major role in their value. Sapphires from certain locations are more prized in the gem trade. Here are the top five sources for fine quality blue sapphires:
- Sri Lanka
- Myanmar/Burma
- Madagascar
- Tanzania
- Kashmir
Sri Lanka (Ceylon) is famous for its beautiful blue sapphires in shades of cornflower, royal, and navy. Burmese sapphires tend to have a deeper royal blue enriched by fine silk inclusions. Sapphires from Kashmir are highly prized for their perfect velvety blue but very rare. Sapphires from these premium localities demand higher prices and add to the stone’s prestige.
Synthetic Sapphires vs Natural
Synthetic sapphires manufactured in labs have the same physical and chemical properties as natural stones, but they sell for much lower prices. Here’s a comparison:
| Synthetic | Natural | |
|---|---|---|
| Origin | Man-made in lab | Mined from earth |
| Cost | Very affordable | Expensive, higher quality |
| Color | Consistent | Varies, some superior |
| Prestige | Minimal | Highly valued |
The biggest advantage of synthetic sapphires is cost savings. They can offer the same blue tones for a fraction of the price. However, natural sapphires offer cachet and investment value that lab stones don’t. Fine natural blue sapphires are worth the higher cost to many buyers.
Enhancing Sapphire Color
Some sapphires undergo treatments to improve their color and clarity. Common enhancement methods include:
- Heat treatment – Intensifies blue color and improves clarity by dissolving inclusions
- Diffusion – Introduces trace elements like titanium to add more blue
- Irradiation – Bombards the stone with radiation to alter color
- Fracture filling – Fills cracks with glass or molten material to improve appearance
Most sapphires are heated, which is accepted in the trade as long as it’s disclosed. Diffusion and irradiation are considered less desirable as they artificially alter the stone’s composition. Fracture filling drastically reduces value. When buying, look for a lab report assessing any treatments.
Matching Sapphire Color to Skin Tone
Sapphires complement most skin tones nicely, but some blue shades pair better than others depending on skin undertones. Here are flattering sapphire hues to match skin tone:
| Skin Tone | Best Sapphire Colors |
|---|---|
| Fair, rosy | Cornflower, sky blue |
| Fair, neutral | Royal blue |
| Medium, warm | Vivid blue |
| Olive, dark | Navy, indigo |
Lighter blues enhance fair skin beautifully. Medium blue sapphires complement deeper complexions like tan or dark skin. Vivid blues work nicely for medium warm skin. Be sure to also consider the metal color – yellow metals pair better with warm skin, while white metals match cooler skin.
Sapphire Color Meanings
In crystal healing traditions, different sapphire colors are believed to have special meanings and powers:
| Sapphire Color | Meaning |
|---|---|
| Blue | Wisdom, loyalty, sincerity |
| Pink | Love, compassion, nurturing |
| Yellow | Optimism, creativity, success |
| Green | Growth, calmness, focus |
| White | Purity, divination, moon magic |
Blue sapphires symbolize fidelity and spiritual enlightenment. Pink sapphires promote tender feelings and nurturing. Yellow sapphires bring wealth and abundance. Green sapphires encourage learning and ambition. White sapphires enhance intuition and magic.
Famous Sapphires in History
Some renowned sapphires have played important roles throughout history:
- Logan Sapphire – Cushion-cut 423 carat sapphire from Sri Lanka, donated to the Smithsonian
- Stuart Sapphire – Enormous blue 104 carat gem owned by King Charles II in 1660s
- Rockefeller Sapphire -62.02 carat sapphire worn by John D. Rockefeller daily
Giant blue sapphires like these adorned royalty in medieval times. Today large natural sapphires are almost unheard of. September birthstones over 5 carats are exceptionally rare and valuable.