The Yellow Variety of April's Birthstone, Diamond

This year at the Oscars the crowds cascaded hushed whispers as Lady Gaga stepped out adorned by the hefty 128.54 carats Tiffany Yellow Diamond. The modified cushion brilliant cut stone has not been worn in public since 1961 when Audrey Hepburn was promoting Breakfast at Tiffany's.

The gargantuan gem usually lives on display at Tiffany & Co.'s New York location under careful security since it is one of the world's largest cut yellow diamonds and possibly the largest diamond on display in the United States.

The quintessential diamond reins as April's birthstone, curating the refraction of light within its facets to exude fiery brilliance. Fancy diamonds, as indicated above, have been gaining popularity as their rarity and aesthetics have become more appreciated. Only one carat out of ten thousand carats will have fancy coloring since basic diamond chemistry typically causes them to be absent in color.

Yellow diamonds are radiant and warm like sunlight captured in stone.  While being incubated deep in the earth's mantle, waiting to be propelled to the surface, nitrogen creeps into the very rigid carbon crystal structure causing the stone to color. The reason nitrogen is available during diamond formation is that it is a byproduct of the plant life cycle.  Many diamonds will have been exposed to varying amounts of nitrogen, but few have the chemistry to accept the element.

Currently, the industry tends to steer people towards colorless and near colorless, but historically a diamond in any shade was valued due to how it captured light. The color grading scale at GIA was not developed until the 1950s so you will see yellow and yellowish diamonds in estate jewelry.

An Art Deco  piece that creates stoic balance as the yellow diamond sits in a classic millegrain frame.

Here is a favorite Oscar Heyman, with a very saturated yellow-orange stone in a ballerina style, simulating movement due to the size variation of the baguette surround.

And finally an example of an ornate Edwardian piece with a soft yellow center.