Sapphire is the second hardest naturally-occurring gemstone, with diamonds being the hardest. These stones can be found in several countries including Burma, Kashmir, Thailand, North America, Brazil, Australia, and Africa. The most recognizable Sapphires are a vivid blue hue, but pink, purple, green, yellow, and even colorless stones can be found.
Regardless of color, all sapphires have a Mohs Hardness of 9 and have a trigonal crystal structure. The most recognized blue color comes from the higher levels of Titanium and Iron; however, other-colored sapphires get their colors from the addition of naturally-occurring elements, including Chromium and Vanadium.
Historically, the blue sapphire was most popular among royalty as a symbol of prosperity and holiness. The Persians believed the earth sat upon a large sapphire, which reflected to make the skies at various times of the day. Later in history, medieval kings wore the stone to the signing of treaties as it was believed to ensure a complete reconciliation between the parties. More recently, Princess Kate wears a sapphire engagement ring and the British Crown Jewels contain several large sapphires as symbols of wisdom and virtue.
Although the sapphire is most commonly represented as the birthstone for September, its use in engagement rings is rapidly growing. In addition to representing prosperity, sapphires also symbolize sincerity and faithfulness, making them an excellent choice for engagement rings. Couples often select sapphires for engagement rings as the stone’s meaning or color is of special significance to the wearer. Additionally, sapphires can be preferred as they do not require any unusual or special care that other gemstones and minerals may require.
When choosing a sapphire for use in an engagement ring, it is important to note that the stones with the strongest, most vibrant hues are considered to be more valuable and will have the highest cost per carat. Although the saturation of the stone should be as intense as possible without darkening its color, the wearer may prefer a darker or lighter color than is traditional. Even though hue is arguably the most important factor to consider when purchasing a sapphire for an engagement ring, Tone, Color-Purity, Clarity, Cut, and Transparency are also crucial components.
Typically, sapphires contain inclusions, or slight imperfections due to silk (fine needles or fine mineral inclusions are known as silk) becoming imbedded during the stone’s formation; however, their overall clarity usually remains high. A skilled jeweler/gemologist will be able to determine the best cut for the stone considering any inclusions that may be present. However, the most appealing cuts have strong symmetry and reflect light evenly, which highlights its vivid color. Stones with deeper cuts will show off more color and preserve the stone’s weights, which increases the cost of the stone. Conversely, stones with shallower cuts will appear significantly lighter in color and may look unbalanced.