The Enigmatic Beauty of Phenomenal Gemstones

Gemstones have long mesmerized people across cultures and generations. They are often viewed as symbols of wealth or beauty. However, a special category of gems stands out for their unique optical properties: Phenomenal gemstones. These gems not only dazzle the eyes with their stunning appearances but also exhibit rare visual effects that elevate them beyond the ordinary. In this post, we will uncover their distinct traits and the fascination that surrounds them.

What Are Phenomenal Gemstones?

Phenomenal gemstones are characterized by exceptional optical effects, resulting from unique internal structures. Unlike regular gemstones, phenomenal gemstones display remarkable visual effects such as pleochroism, chatoyancy, asterism, and color change. These effects are a result of inclusions (materials other than the chemical compound of which the gem is composed) or unique arrangements of atoms in crystal formations.

Understanding the scientific basis for these phenomena adds to our appreciation of these gems:

• Cat's Eye (chatoyancy): This gemstone features a narrow band of light moving across its surface, reminiscent of a feline's slit-like eye. The effect arises from fine, parallel fibers within the stone. A high-quality cat's eye can command prices of $1,000 per carat or more, especially when it exhibits a strong effect. Tourmaline, chrysoberyl, tiger's eye in both gold and red, hawk's eye (one of my very most favorite stones) aquamarine, selenite, feldspar, apatite and scapolite are just some of the stones known to exhibit this effect.

  
  

• Asterism (star effect): Known for its stunning star-like appearance, star corundum (sapphire and ruby) and star quartz showcase a pattern created by light reflecting off of needle-like inclusions. which intersect at 60 degrees creating a 6-rayed star on the surface of the gem. Still more rare are 12-rayed star corundum. Star garnet and star diopside display stars with only 4 rays. The best asteriated sapphires display a highly visible star and can reach values of up to $7,500 per carat, depending on quality. Beware: Synthetic star sapphires and rubies are very, very common.

  
  

• Color Change: Famous for their ability to change color under different lighting conditions, alexandrite, certain garnets, sunstone, kunzite, fluorite , spinel and other gems appear to be one color in fluorescent light, another color in incandescent and sometimes a third color or shade of color in outdoor daylight. Many gems appear to be the color they are because they reflect light of that color back to the viewer. However, fluorescent light is deficient in red and orange wavelengths, while daylight contains the full spectrum Therefore, if fluorescent light contains insufficient red wavelengths to be reflected back to the viewer's eye, the gem is going to appear to be color other than red or a weaker shade of red. This shift can be quite remarkable, turning a green stone to a vivid red, for instance.

  
  

• UV Reactivity: Many gems also react to ultraviolet light. Sapphire, ruby, opal (one of my most favorite stones to cut), certain diamonds, aragonite, fluorite, calcite and many others will fluoresce a different color or shade of color than what is seen in day- or indoor-light when they are exposed to ultraviolet wavelengths. Daylight contains UV wavelengths and, if you take a ruby outdoors, it will be noticeably brighter and oftentimes will appear to be more of a true red color. Some gems will continue to glow in the UV-exposed color even after the UV light source is removed. This is called phosphorescence and can be seen in fluorite, kunzite and certain diamonds. Many collectors focus on UV-reactive gems only.

  
  

• While not technically phenomenal, pleochroism causes a gem to appear to be different colors depending upon the angle at which it is viewed. Rotate certain sunstones 90 degrees and they will change from red to green. Iolite is colorless to yellow along one axis, blue to purple on another and brown on a third axis. while tourmalines can be virtually any color on each of three different axes! Fluorite, tanzanite, hiddenite and others fall in this category, as well.

• In exceedingly rare instances, gems may exhibit more than one phenomenon. My wife has a piece of rough red sunstone in our bank safe deposit box which is both pleochroic AND color-changing (which I need to cut soon). It is a red sunstone which, when rotated 90 degrees displays a beautiful medium green AND the red axis also changes color to green when moved fro indoor to outdoor lighting.

The Allure of Phenomenal Gemstones

The attraction of phenomenal gemstones goes beyond their striking looks. They are steeped in stories and cultural beliefs. Many societies regard these gems as tokens of luck or protective amulets.

For instance, cat's eye is often viewed as a talisman against evil spirits, said to bring good fortune to its wearer. Star sapphires are believed to offer guidance and clarity, especially during turbulent times. Alexandrite is associated with prosperity and creativity, making it particularly popular among artists and innovators.

Star Sapphire showcasing its captivating star effect.

Choosing and Caring for Phenomenal Gemstones

When selecting phenomenal gemstones for jewelry or personal collections, consider the following points. Look for stones with high clarity and vivid colors. In general, larger and more distinct phenomena, like the brightness and visibility of the star in a star sapphire, tend to be more valuable.

Taking care of these exquisite gems requires the same practices that should be used for all gems: Avoid harsh chemicals and extreme temperatures that could damage the stones, and always store them separately to prevent scratching.

Investing in Phenomenal Gemstones

For both gemstone lovers and collectors, investing in phenomenal gemstones can be rewarding. Their rarity and unique features can lead to increased value over time. However, research before investing is essential to verify the authenticity and quality of any gemstone before purchasing. Only consider investing in stones from reputable dealers, such as Romano Gems, to ensure you are buying genuine pieces.

Alexandrite exhibiting its remarkable color-changing ability.