Natural fancy colored diamonds are very rare and expensive and blue diamond is one of the rarest and most desirable colors. The Hope diamond, which can be viewed in the Smithsonian Institute in Washington D.C., is the most famous blue diamond in the world, and the largest with ca. 45.52 carats weight!
In recent years, methods of producing intensely colored diamonds, including fancy blue diamond have made considerable progress.. The process is believed to recreates the conditions which existed millions of years ago to produce natural fancy colored stones. The treatment can only work with a small minority of diamonds, and involves irradiating them causing the color change, usually followed by heat treatment to stabilize the color.
Blue Diamond Versus Sapphire
Question has often been asked whether blue sapphire is appropriate substitute for blue diamonds, The very best sapphires are also expensive, and they do not have the sparkle that blue diamonds possess. In addition even though sapphires are very hard and durable, diamonds are many times harder and even more durable.
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