Star Sapphire Gemstone: A Comprehensive Guide

We are probably all familiar with the beautiful sparkling face of the traditional blue sapphire. But this article will focus on a lesser-known variety of sapphires: colored star sapphires. These refer to gemstone-grade sapphires that feature a white or golden star across their center. This pattern is called ‘asterism’.

In this guide, we are going to look at star sapphire gemstones in detail, including how to care for a star sapphire.

About Star Sapphire

A star sapphire is a jewel that displays asterism, and is one of only four gems considered a precious gemstone. Additionally, they are the birthsone for September and are associated with three different wedding anniversary gifts: the 65th, 45th, and 5th.

Star Sapphire Characteristics and Specifications

A star sapphire usually has a silky luster with an opaque asterism that is most visible in direct light. The pattern is caused by light bouncing off mineral rutile inclusions within the gemstone. The rutile inclusions are mostly composed of titanium dioxide which causes a white color.

In order to highlight the star, the gemstone is often cut into a high-dome cabochon. The unique shape makes the gemstone stand out in any jewelry piece. While this sapphire is quite stunning, its uses go beyond just pretty jewelry. Some of the meanings associated with this sapphire relate to protection from evil and illness.

As with traditional sapphire gemstones, the star sapphire is available in more colors than just blue. Colors like yellow, orange, and pink sapphire stars are also available. They are mined in Malawi, Zimbabwe, Rwanda, Pakistan, China, Kenya, Vietnam, Tanzania, the United States, Madagascar, Cambodia, Brazil, Sri Lanka, Thailand, Myanmar, and Australia. All sapphire is composed of the mineral corundum.

We have outlined some important gemstone identification points for star sapphires below:

• Streak: White (although Thailand varieties have a golden star)
• Fracture: Conchoidal with parting in many cases.
• Transparency: Opaque is common, some transparency might be present.
• Luster: Adamantine (diamond-like) to Vitreous (glassy).
• Color: All except red.
• Mohs hardness: 9

Star Sapphire History and Meaning

This gemstone is often called the ‘gem of heaven’ and is associated with hope, potential, and dreams. Protection is a common association while some feel that this gemstone represents a higher sense of spirituality and clairvoyance. In Christianity, the star sapphire is also sometimes referred to as the ‘Stone of Destiny’.

History

In the past, the star sapphire has been called the ‘asteria’, so it is seen as the gold standard, and a well-defined star is often visible. One of the earliest specimens of these gemstones to be unearthed was the Star of India. It was found in Sri Lanka and weighed in at 563.35 carats. This is one of the biggest gem-quality blue sapphires in the world that has the star effect. It was dated by the American Museum of Natural History at about 2 billion years of age.

The Star of Adam is currently the biggest blue star sapphire ever found. It was also mined in Sri Lanka and weighs 1,404.49 carats. The Black Star of Queensland is the second-largest star sapphire in the world. This 733-carat sapphire was found in 1938 in Australia.

Star Sapphire Healing Properties

Star sapphires are often associated with opening the chakras. They are also considered healing stones. Other things that the sapphire is associated with include:

• Enhancing psychic powers.
• A sense of purpose.
• Mental acuity.
• Recovery from injury or illness.
• Protection from evil or illness.

Gemstone Properties of Star Sapphire

When it comes to grading special gems like a star sapphire, there is more involved than just the gem’s carat weight, clarity, cut, and color. You also have to factor in the quality of the asterism and the rarity of the stone. High-quality star sapphires are exceedingly rare, so their value can be quite high when they do appear on the market.

While both natural and artificial gemstones occur, only professional jewelers can tell the difference between the two. The most obvious difference is that lab-created star sapphires tend to look too perfect to be real. Natural gemstones can also undergo treatments that will make the colors and the stars more intense. The treatments themselves can also artificially induce the famous star effect. A particularly high-quality star sapphire has very likely received heat treatment.

Simulants and Synthetics

There are some ways that you can tell whether your star sapphire is lab-created or natural.

With synthetic star sapphires:

• The star does not move when the stone is moved around.
• Sometimes there is an ‘L’ stamped on the bottom.
• The color is distributed evenly and is very bright.
• There aren’t any imperfections.
• The star is uniform and flawless.

A simulant star sapphire often has a star rose quartz in it with a blue backing.

Carat Weight and Size

Although we have talked about some record-breaking star sapphires, most of the stones are actually quite small. Larger ones are usually black star sapphires. The price-per-carat tends to increase for a star sapphire between 1 and 5 carats, and 0.5 to 1 carat.

Asterism: Centering and Visibility

Asterism is graded according to the centering of the star’s visibility.

Clear visibility with bright rays is important. Less value is placed on broken, wavy, or muddled stars. When the star is bright and centered on the cabochon then the value is also increased.

The very best stars:

• Contrast strongly with the sapphire color.
• Are uninterrupted.
• Run from girdle to girdle.
• Are centered on the stone.
• Are smooth.
• Are intact.
• Have straight arms.
• Are uniformly bright.

With a natural stone, the star will move elegantly and smoothly when the stone is rotated. Also, remember that not all of the value lies in the brilliance of the star. The sapphire’s color and translucence also add to the value.

Transparency and Clarity

The clarity of sapphires is never entirely perfect. It is not uncommon for there to be minor visible inclusions. While the star itself is caused by inclusions, any inclusions that obscure the star or affect the body color of the sapphire will lower the value. How translucent the sapphire is will also impact the price. Perfect stars on natural sapphires are almost unheard of, so many of the better specimens are man-made.

Cut

In order for the asterism to display, star sapphires are always cut as cabochons. When the star is centered, then the cabochon cut is considered of high quality. Where the girdle of the cabochon is can impact the effect of the stone and can sometimes appear as a cat’s eye. Proper cutting is, therefore, essential to preserve the image of the star.

Color

Like any other sapphire, star sapphires are available in all colors except red. Blue, black, and pink star sapphires are quite common, whereas orange and yellow are rare. Blue sapphires, whether they are a star sapphire or not, are the most valuable. Usually, the star is gray or white. With black star sapphires the stars can also be gold. Furthermore, these gemstones are not actually black. They are usually yellow or blue but can appear brown or black due to inclusions.

Saturated colors on a star sapphire carry a higher price than muted colors. One of the reasons for this is that bright star sapphire colors result in a clearer contrast with the star – making it more visible and resulting in a more eye-catching piece of jewelry. Some colors are also more popular in general. For example, a blue star sapphire ring is more popular than the same in orange.

The star quality in any gemstone is exceedingly rare. It is not something that commonly occurs in nature, so only a handful of sapphires have this quality. There are also other gemstones that can have stars, for example, a star garnet or ruby. What sets sapphires apart, however, is where they sit on the Mohs hardness scale. Diamonds measure a 10 – putting them at the very top of the scale. Sapphires are a close second at a 9.

Star Sapphire Color Varieties

Purple Star Sapphire

These unique gemstones are something quite special. They are often accompanied by a diamond or other white stone. Engagement rings with this kind of star sapphire can cost anything between $2,000 to $4,000 when verified by the Gems Research Center. When there are diamonds on the ring as well the price will increase. The size of the gem and the setting in which it is in will also impact the price (this is because platinum, white, and yellow gold all fetch different prices).

Green Star Sapphire

As mentioned, some star sapphire colors are very uncommon, and green is by far the most uncommon. This makes the price for one of these gemstones extremely high. It is actually unclear why star sapphires in this color are so rare. Generally speaking, the color is caused by the amount of iron in the stone. There are also different shades of green, most of them light and slightly yellow, but color saturation does not impact the price of green star sapphire stones much.

White Star Sapphire

While green and pink star sapphires are quite rare, white ones are common. As a result, white star sapphires are not as expensive as the other colors. Common jewelry items that feature white star sapphires include engagement rings, necklaces, and earrings. When looking to purchase a white sapphire, it can be very difficult to tell a lab-made sapphire from a natural one. So, if this is important to you, make sure to check before you buy.

Pink Star Sapphire

Strictly speaking, any precious stone made from the mineral corundum that is purple, pink, or red is a ruby. Thus, the distinction between pink sapphires and rubies is often blurred. So, what you might find is that a stone will be labeled a pink sapphire in one jewelry store and a ruby in another.

That being said, you will find that most jewelry stores only classify deep red stones as rubies. This means that any corundum gem in a shade of pink will be labeled a sapphire. These stones typically command high prices given their rarity in nature, and the price will usually increase for any pink sapphire that comes from Sri Lanka, where the purest gemstones are often found.

Red Star Sapphire

As mentioned, red sapphires are called rubies. However, we have included them in this discussion to be thorough. After all, both sapphires and rubies belong to the corundum mineral family of gems. The red color is a result of trace elements like chromium in the crystal lattice of the jewel. Another type of red star gem is the star garnet, which is frequently mistaken for ruby.

One major difference related to the classification of these gemstones is that sapphires can range from black to green and blue, whereas rubies are always a shade of red. This includes the star ruby. In comparison to other precious gemstones, a star ruby is much cheaper per carat.

Blue Star Sapphire

Blue star sapphires with a clear star are rare, which means they command premium prices. Because these gemstones are generally not readily available in nature, there is a significant market for lab-made stones. As more of these are made available, the price will gradually decrease. While natural sapphires are more sought after, lab-made stones are still genuine and should not be frowned upon.

Star Sapphire Care and Maintenance

Sapphire is a fairly durable gemstone but fractures are still possible when there are a lot of inclusions. Special treatments for filling fractures are available and serve to strengthen weaker stones.

Regardless of the quality of your sapphire, we advise keeping it away from abrasive cleaning machines and harsh chemicals. If your star sapphire is set in a ring, we also suggest opting for a protective setting. Exposure to extreme heat and acidic cleaners can also damage your stone. We suggest using mild soap, warm water, and a soft toothbrush to keep your stones sparkling and clean without damaging them.

Star Sapphire Price Guide and Value

The price of most star sapphires is determined by their quality. Specifically, the gemstone properties of star sapphires are extremely important as the prices can range between $10 to $10,000 per carat.

So, how much is a star sapphire worth in general?

• Black varieties: Between 0.5 and 5 carats you can expect to pay between $10 and $30 per carat.
• Blue varieties: Between 1 and 5 carats you can pay anything from $300 to $1,200 per carat. Between 0.5 and 1 carat you can pay around $20 to $100 per carat.
• Fancy color varieties: Between 1 to 5 carats you can pay between $100 and $500 per carat. Between 0.5 and 1 carat you can pay around $100 to $300 per carat.

The most expensive variety is the pure blue Kashmir sapphire with a clear star.

Mining Locations

At times, the mining location of star sapphires also slightly impacts their price. The best star sapphires come from Myanmar and Sri Lanka, but they have also been found in India, Cambodia, Thailand, and Canada.