The diamond has been the symbol of everlasting love for centuries now, and the beautiful gem continues to dazzle all who become captivated by its brilliance. Colored diamonds have also slowly emerged as exceptional beauties for their unique chemical makeup. The blue diamond is the rarest of the gems and has become the most sought after as its shade can range from baby blue to deep ocean blue. The blue diamond happens to have an incredible birthplace, reports Popular Science, one that extends far below the earth from a billion years ago.

A study recently conducted by the journal Nature has discovered that the blue diamond is the deepest of the diamonds and may actually possess an origin from the sea. The journey for this stunning gem, however, is a bit more “rocky” and complicated. In addition, these blue beauties are so scarce, they cannot be easily studied when searching for answers. It is estimated that only about one in 200,000 diamonds display even a tiny amount of blue.

Experts who know all about diamonds understand that carbon is the leading element in the making of the gemstone. The typical clear diamond is comprised of a transparent crystal of tetrahedrally-bonded carbon atoms. The blue diamond has an even more exotic background; it also contains the element of boron. These atoms become trapped in the crystal’s lattice structure and give the luxe intensity of blue to the stone.

Boron is contained in high amounts in the earth’s surface, so it’s baffling how the chemical element could be found in blue diamonds forming four times deeper into the immense depths of the earth. Scientists believe that the earth performs a bit of natural recycling, concluding that the boron atoms must have sunk into the mantle when tectonic plates slipped beneath each other. The boron minerals continued their trip along with ocean water, combining with carbon in extreme pressure and heat and crystallizing into the rare blue gems. Eventually, volcanic action brought the diamonds up closer to the surface.

The Hope Diamond is an iconic blue stunner with 45.5-carats valued at around $350 million. It was once owned by Louis XIV, Marie-Antoinette and George IV.

The color blue is beautiful and very expensive, but the sparkle and intrigue are priceless.