A little about Blue Sapphires
Sapphire is a precious gemstone, of the mineral corundum variety. When it comes to precious gemstones, blue sapphires have long been sought after, as they carry significant meaning. These stones have been associated with royalty for several centuries already.
Blue sapphire exists in various mixtures of its primary (blue) and secondary hues, various tonal levels (shades) and at various levels of saturation (vividness). Blue sapphires are evaluated based upon the purity of their blue hue. Violet, and green are the most common secondary hues found in blue sapphires. The highest prices are paid for gems that are pure blue and of vivid saturation. Gems that are of lower saturation, or are too dark or too light in tone are of less value. However, color preferences are a personal taste, like a flavor of ice cream.
How are Blue Sapphires Priced?
Sapphires can range in price depending on a number of factors. Blue Sapphire stones are the most valuable naturally blue-coloured gemstones in the world. They are sought after due to the depth of their colour, their hardness (which is second only to that of diamonds), their durability and their ability to sparkle in the light – a phenomenon known as lustre.
Sapphires are sold from anywhere from US $25 per carat to well over US $11,000 per carat depending on colour and inclusions. The stone’s prices are generally determined based on quality, meaning that a larger, lower-quality stone could be much cheaper than a smaller one that’s of a higher quality.
A little about Alexandrite
Often described by gem aficionados as “emerald by day, ruby by night,” alexandrite is the very rare color-change variety of the mineral chrysoberyl. Originally discovered in Russia’s Ural Mountains in the 1830s, it’s now found in Sri Lanka, East Africa, and Brazil, but fine material is exceptionally rare and valuable. If not for alexandrite’s popular associations, the circumstances necessary for its formation, combined with its mining history, might have ensured the gem would be little known as well as extremely rare. To form, alexandrite requires both beryllium (Be), one of the rarest elements on Earth, and chromium (Cr). (Emerald also requires these two elements).
Because of its scarcity, especially in larger sizes, alexandrite is a relatively expensive member of the chrysoberyl family. It shares its status as a June birthstone with cultured pearl and moonstone.
How are Alexandrite priced?
Alexandrite have two primary value drivers. First, the closer the colors to pure green and red, the higher the value. Second, the more distinct the color change, the higher the value. Alexandrite can exhibit everything from 100% to just 5% color change. Thus, the most valuable gems would have a 100% color shift from pure green to pure red. Blue-greens and purplish or brownish reds hold less value.
Size always affects alexandrite value. In sizes up to one carat, top-quality natural gems can sell for up to $15,000 per carat. Over one carat, the prices range from $50,000 to $70,000 per carat! Clarity also plays a significant role in grading. As is the case with a majority of gems, most naturally occurring alexandrite isn’t clean, facetable material. Most is best suited for cabbing. However, an alexandrite’s color change has more effect on its value than its clarity. For example, take two alexandrite of equal size. One gem is eye clean, with a 50% greenish blue to brownish red color change. The other is an opaque cabochon with a 100% green to red color change. The opaque cab would be considered more valuable.
A little bit about Rubies
Ruby is a mineral of very limited distribution. The ruby gemstone is composed of transparent red corundum, a mineral form of aluminum oxide. Generally, gemstone-quality corundum in all shades of red, including pink, are called rubies. Its colour varies from deep cochineal to pale rose red, in some cases with a tinge of purple; the most valued is a pigeon-blood red. However, in the United States, a minimum color saturation must be met to be called a ruby; otherwise, the stone will be called a pink sapphire. Its best known localities are in north-central Myanmar (Burma), northeast of Mandalay, where the gemstone occurs in bands of crystalline limestone associated with granitic and gneissic rocks. Rubies have been found at several localities in Thailand, in gravels with sapphires and spinels; they are generally of dark colour, often inclining to a deep reddish brown. The most common use for rubies is jewelry—stunning jewelry! However, both natural and synthetic rubies are used in a variety of applications—such as watchmaking, medical instruments, and lasers—because of their incredible strength and red fluorescence.
Since ancient times, rubies have symbolized passion, protection, and wealth. Many cultures have strong ties to it being a symbol of love and commitment, making it a great gemstone for a wedding ring. In modern times, ruby is the birthstone for July. It’s also the traditional gift for 15th and 40th wedding anniversaries.
How are Rubies Priced?
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 (Color, Clarity inclusions, Cut, Carat Weight). One of the most expensive rubies ever sold is the Sunrise Ruby, selling for over a million dollars a carat at 25 carats.