02/03/2014 04:16 pm ET Updated Apr 05, 2014

Groove is in the Heart

The heart, long considered to be the symbol of love, is the ubiquitous icon of Valentine's Day, appearing in the form of red-foil wrapped chocolates and diamond jewelry. But how did the life-sustaining, blood-pumping organ come to be associated with love in the first place? And how did the red organ become the iconic shape we know today, which is not anatomically correct, but found everywhere from "I <3 NY" t-shirts to emoticons on the web. And finally, what do you need to know about buying a heart-shaped diamond (which is, after all, the most popular diamond shape to be gifted on V-Day)?

According to the ancients, the heart organ was crucial to the body and soul. The ancient Egyptians believed it was the center of life and morality and even incorporated it into their understanding of the afterlife. The ancient Greeks understood that the heart was the most important organ, that the heart was the center of the soul, and according to Aristotle, it controlled reason, thought, and emotion.

It's no wonder, then, that the heart came to be associated with love, as love is one of the strongest emotions. The organ as a metaphor for love developed in the Middle Ages when artists began depicting the four-chambered muscle, according to medieval anatomical descriptions, as a symbol both of romantic love, as in a kneeling lover offering his heart to a damsel, as well as religious devotion, as in the allegory of charity offering her heart to Christ. During the Middle Ages, the "Sacred Heart" of Christian theology became a symbol of Jesus's love, and was often depicted emitting light and pierced by a cross, or surrounded by thorns as in the vision of Saint Margaret Mary Alocoque.

The iconic heart shape that we associate with love, as opposed to the organ, first appeared around the early 14th century in artistic depictions in Italy and Belgium, as well as playing cards by the 15th century.

There are many theories as to the source of the shape. Some believe the shape comes from ivy and water lily leaves, which symbolize longevity and endurance, and are found on ancient Greek pottery and medieval iconography. Other, more modern-era interpretations, claim that the shape resembles the seed of the silphium plant, which was used as an ancient contraceptive. Still others see the famous shape as reminiscent of the female anatomy though it's doubtful whether such a contemporary reading holds any truth.

In any case, the popularity of the shape and its use as a symbol for love became widely popular, so that by the 19th century, the heart shape had become the symbol of romantic love, thus gracing St. Valentine's cards, and other tokens of love. And this is when the heart-shaped diamond began to appear in royal jewelry.

According to legend, Mary Queen of Scots sent a heart-shaped diamond ring to Queen Elizabeth in 1562. Sending a heart-shaped diamond to royalty was seen as a sign of friendship and generosity since heart-shaped diamonds were quite rare, difficult to cut, and highly cherished.

Today this diamond shape is considered to be the most romantic of all the shapes and has become synonymous with Valentine's and anniversary jewelry gifts. Essentially a pear-cut diamond with a notch removed at the top, the heart-shape's brilliant cut contains nearly sixty facets that truly make it sparkle with fire. What's most important to consider when buying a heart-shaped diamond is the shape. Judge with your own eyes to see if both sides are symmetrical and if the overall contours are pleasing to you. There are both skinny-point hearts and wide, fat hearts, but there's no way to tell the difference just by looking at the diamond's certificate. It's essential to view the diamond either in person or in a high-quality image.

So whether you believe that the heart in your body is the seat of your soul or just the red organ you need to survive, it's clear that this cardio powerhouse has taken on metaphorical meaning, as well as having its very own iconographic, ubiquitous symbol. From a symbol of religious devotion in the Middle Ages to a shape familiar to every preschooler today, the heart is everywhere. Get ready to see more of it this February 14, and if you're lucky, it might be staring up at you from a little black box, smiling at you with radiance and charm.

Subscribe to the Lifestyle email.
We’re basically your best friend... with better advice.