Sapphire, with its hardness of 9 on Mohs hardness, is second only to diamond, which renders it one of the most valuable and wearable gemstones of all-time. Sapphire is a 'precious four' gem and offers superb brilliance and rich, vibrant colors. Although most sapphire is heated or enhanced in other ways to improve color, clarity and stability, unheated and completely untreated natural sapphire can still be found. Usually unheated sapphire gems are found only in small sizes, but occasionally, large, clean stones are uncovered too. Because unheated sapphire is such a rarity, they are indeed relatively expensive, particularly unheated top-color blue 'Ceylon' sapphire. Unheated, natural sapphire is mostly sourced from Africa, though Australia and parts of Asia are known to produce some fine materials too.
As of recent times, Madagascar and Tanzania are two of the most important sources for fine untreated, unheated sapphire, as is Thailand. Tanzanian sapphire is usually pink to violet in color (often violet-blue), and many of the specimens exhibit very noticeable color change properties. Color-change unheated sapphire can be very expensive and is highly sought-after by both jewelers and gem collectors. Fine quality unheated sapphire gems from Madagascar, as well as Australia, display silk inclusions, which are highly desirable. The silky appearance is cause by rutile inclusions and the presence of such silk is usually a good indicator that the gem has not been heated, since rutile inclusions melt at a much lower temperatures than those at which sapphire is heated. Sapphire is also the official birthstone for those born in the month of September.
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Site was recommended to me by my gemology professor. Based on what I’ve seen gemselect offers good quality stones for a large range of prices
Ive been shopping here many times before, so navigating around was easy. I am accustomed to the quality of the items and that's the main reason I come here. When I need non heated stones I know I can count on GemSelect being authentic. I trust them because I double check their quality. And never had problems with them. And yes I do recommend shopping there to some of my clients who are "less knowledgable" of industry. GemSelect is so user friendly they're great for beginner gem shoppers!
Well fell in love with the site right away ordered two many items I knew I would return a few. Decided I wanted to invest in a sapphire emerald or ruby after more research. The diamonds that I received we just stuck together just ordered one more I will have 10 in all diamonds two yellow six white. I'm so very happy I didn't know what I was going to keep and definitely diamonds were winner.