Unless they aren't, diamonds are a girl's best friend. A whopping 86 percent of consumers purchasing an engagement ring choose a diamond as their center stone, but 14 percent choose a non-diamond alternative and that percentage is likely to increase, as looking for something unique is important to lots of Millennials and Gen X'ers.

If you're looking for something a little unusual, and unique to you, we've got some terrific engagement ring ideas for you (and can help you find the perfect example from among our huge selection of gemstones)

Emerald Engagement Rings

The fact that brilliant green emeralds are stunning in every light, and every situation, and each emerald is unique, both in terms of color and the slight inclusions that almost every emerald engagement ring will include and that add to its beauty rather than detract from it, the emerald also boasts a long and storied history as a symbol of love.

The Romans are credited with popularizing emeralds as a gemstone connected with love. Emeralds were thought to be sacred stones of the goddess Venus-Aphrodite, whose divine qualities included love, beauty, fertility, and prosperity, according to the Romans.

Venus-Aphrodite was said to have been created from sea-foam in Greek mythology. Venus-Aphrodite was a powerful female force, according to Roman mythology. Venus absorbed and tempered the male essence, bringing the male and female opposites together in mutual love. As a result, Venus' emeralds were supposed to protect love from misfortune. This makes them an excellent choice for an engagement ring.

Sapphire Engagement Rings

The 18-carat sapphire engagement ring that Prince Charles gave to Princess Diana is the most iconic engagement ring in contemporary history. And it was this gift that Prince William gave to Kate Middleton many years later when he proposed.

The sapphire engagement ring given to Empress Josephine by Napoleon may have begun the royal tradition. And sapphires are not even always blue, as Princess Eugenie's sapphire engagement ring is a pink-orange padparadscha sapphire that is truly stunning. This means that a sapphire engagement ring is not only beautifully unusual, but also majestic.

Amazing set of rings

Amazing set of rings

Ruby Engagement Rings

The color red has long been connected with our most powerful emotion: love. Consider this: hearts and roses are both red. Valentine's Day is dominated by the color red. Rubies, being the most popular red gemstone, have long been associated with unwavering love and devotion.

Throughout history, the ruby has held a prominent position and has been revered by everybody. Rubies are known as the "king of gemstones" in the ancient Sanskrit language. Rubies were worn by ancient peoples in the hopes of attracting love, success, wealth, and good health.

Rubies are still highly prized and appreciated today. Their meaning is ideal for an engagement ring gemstone, and their rich reds are a stunningly beautiful choice too.

Morganite Engagement Ring

If you want a really beautiful, but certainly very unusual, gemstone engagement ring, a morganite engagement ring could be the perfect choice. Morganite belongs to the beryl family of gemstones and is named after the famous banker and gemstone aficionado J.P. Morgan. It's a cousin to emerald, goshenite, and aquamarine and is composed of aluminum beryllium silicate. It's also known as rose beryl or pink emerald.

Traditionally morganite has symbolized warmth and fidelity, both great meanings for an engagement ring to project, and it is also loved for the fact it compliments and enhances a wide range of skin tones, another important factor to consider when choosing the perfect engagement ring for you.