Sapphires Formed
Sapphires, preceded only by diamonds, are the most commonly sought colored gemstones. Known for their rich blue color and rarity, they are cherished. These precious gems form under specific earthly conditions. While blue is their most well-known hue, sapphires can also be found in a spectrum of colors such as yellow, pink, orange, and white. Humanity has long delved into the Earth in search of these treasured gemstones for millennia. Sapphires are particularly valued for their vibrant color, durability, and rarity, making them popular choices for various types of jewelry, including earrings, necklaces, and rings.
Sapphire Origin & Formation
Sapphires are a rare gem needing millions of years to develop. Much like rubies, sapphires are created from the mineral corundum, scientifically known as aluminum oxide. During formation, corundum attains its color through the presence of various other minerals. Sapphires are commonly located in recrystallized limestone and metamorphic rocks with low silica content but high aluminum concentrations. As the crystal lattice of sapphire forms, the infiltration of transition minerals can alter its color from white and transparent to various other hues.
Colored Sapphire Formation
Due to this process, sapphires appear in many colors and even multiple shades and combinations like orange and pink. Any corundum taking on a non-red hue is classified as sapphire. Different combinations of minerals result in different colors, providing a variety of sapphires including pink, yellow, and, most popularly, blue. With iron, sapphires become yellow; with vanadium, they turn purple.
Blue Sapphire Formation
The blue sapphire, the most popular variety, forms due to the presence of titanium in the corundum rock. Corundum is found within igneous rocks, and the slow cooling of these rocks allows large mineral crystals to form from magma. The purest sapphires emerge from igneous rocks undergoing transformation. The slower the magma cools, the larger the sapphires. However, this ideal cooling condition is rare due to frequent changes in pressure and environmental factors during cooling. Each sapphire, therefore, possesses a unique look and color, with inclusions and impurities giving each one a distinctive fingerprint. No two natural sapphires are identical.
Large sapphires are rare due to the long and specific conditions needed for their formation. Natural sapphire deposits in the Earth often have a barrel shape, longer and tapered at the ends, but broader in the center. Once mined, sapphires can be cut into various shapes for jewelry. Sapphire ranks very high on the Mohs scale, at 9, with only moissanite and diamond being harder. This high durability is due to short, strong bonds between oxygen and aluminum. Sapphires’ hardness, combined with their vibrant colors and brilliance, has made them highly valued across cultures and civilizations.
Sapphire Origin
Sapphire deposits are found in Myanmar, Sri Lanka, Madagascar, Thailand, China, Australia, Nepal, Nigeria, Pakistan, Kashmir, and Montana. Around 150 million years ago, intense pressure and heat created sapphire deposits deep within the Earth’s crust, typically 6 to 18 miles beneath the surface. Over time, weathering and natural movements of the Earth’s surface revealed these deposits. Only a few places globally are now known to expose these sapphire deposits after extensive weathering. The properties and inclusions of sapphires can vary based on their location, leading to different types and qualities. Sapphires worldwide can be classified into three main categories based on their formation: classic metamorphic, non-classic metamorphic, and classic magmatic.
Historically, sapphires from Kashmir, Burma, and Sri Lanka have been the most coveted. Burmese sapphires, often found in marble, are prized for their exceptional clarity and quality. Geographically, significant sapphire deposits exist along the boundary where the Indian sub-continent collided with the Asian landmass, generating intense heat and pressure, forming sapphire deposits. Over time, natural water streams and rivers revealed these deposits. While traditional regions in the Asian subcontinent were highly regarded for their superior sapphires, Madagascar has recently taken the lead in production, having surpassed Australia in the 1990s. In the United States, Montana and North Carolina are known for producing sapphires, notably the Montana and Yogo sapphires with a slightly lighter blue hue. Sapphires from various origins are treasured globally and chosen based on personal preference for variety and shade.
More about Sapphire Formation: Crystallization and Inclusions
Sapphire crystallization occurs in two stages, starting with the nucleus formation, followed by successive layers of minerals being added over time. If environmental conditions halt sapphire formation, the nucleus may break apart. Structurally, the sapphire forms in a…
When mined, sapphires commonly exhibit a barrel shape due to their formation process. Most sapphires contain inclusions, with rutile inclusions often appearing as tiny crystalline growths inside the stone during its formation. These inclusions help differentiate natural sapphires from synthetic ones. Additionally, the vast majority of natural sapphires undergo heat treatment to enhance their color, a permanent process. Untreated, inclusion-free natural sapphires are exceptionally rare and command a high price. Artful Bracelets guarantees the use of high-quality blue sapphires, meticulously checked for their brilliance and color. We source our sapphires from reputable suppliers committed to ethical and trustworthy mining practices.
FAQs
Where are sapphires generally found?
Sapphires are sourced from various locations including Myanmar, Sri Lanka, Madagascar, Thailand, China, Australia, Nepal, Nigeria, Pakistan, Kashmir, and Montana. Notably, Sri Lanka and Kashmir are famous for their sapphire deposits.
What is the difference between natural and lab-created sapphire?
Lab-created sapphires share the same physical and optical properties as natural sapphires, including hardness. The primary difference is their origin: natural sapphires form underground over millions of years, while lab-created ones are made in a controlled environment within days. Natural sapphires often have inclusions and flaws, whereas lab-grown sapphires are usually flawless. Consequently, lab-created sapphires tend to be less expensive.
How much are sapphires worth?
Sapphires can range in price from $25 per carat to over $11,000 per carat, depending on quality. Larger, lower-quality sapphires are less expensive than smaller, high-quality ones. The most prized variety is the cornflower blue Kashmir sapphire. Other rare and valuable types include the orange-pink Padparadscha sapphire and the color-changing sapphire, which shifts hues under different lighting.
Are sapphires more expensive than other gemstones?
Sapphires are generally less expensive than diamonds, rubies, and emeralds. For instance, a good-quality 1-carat ruby can be priced around $1,000, while a high-quality 1-carat emerald may cost between $500 to $1,000. Sapphires can vary from $25 to $11,000 per carat based on quality.
