Purple gemstones capture attention with their rich and varied hues, ranging from soft lavenders to deep, majestic violets. These captivating stones have been admired for centuries, symbolizing creativity and luxury. Their diverse beauty makes them popular for jewelry and ornamental pieces.
Common Purple Gemstones
Amethyst stands out as the most recognized purple gemstone, a variety of quartz. Its color spectrum ranges from delicate pale lilac to intense, dark violet. Amethyst rates a 7 on the Mohs hardness scale, making it suitable for various jewelry types. It commonly forms within geodes or as individual crystals.
Tanzanite presents a distinct blue-violet to purplish-blue appearance, known for its strong pleochroism. This rare gemstone is found exclusively in a mining area near Mount Kilimanjaro in Tanzania. Tanzanite has a Mohs hardness of 6 to 7.
Purple sapphire, a member of the corundum mineral family, showcases a wide range of purple tones, from light pastels to rich, saturated shades. Sapphires are highly durable, ranking 9 on the Mohs scale, second only to diamond. Deposits of purple sapphire are found in locations such as Sri Lanka, Madagascar, and Myanmar.
Sugilite is another striking purple gem, characterized by its vivid purple color, which can vary in intensity. This gemstone’s coloration is attributed to its manganese content. Sugilite has a Mohs hardness of 5.5 to 6.5.
Iolite, often called “water sapphire,” exhibits a captivating violet-blue color due to its strong pleochroism. This silicate mineral contains iron and magnesium, contributing to its hues. Iolite has a Mohs hardness of 7 to 7.5.
The Science Behind Purple Hues
The purple color in gemstones primarily results from the presence of specific trace elements within their crystal structures. These elements act as impurities, altering how the mineral absorbs and reflects light. For instance, amethyst’s iconic purple is caused by trace amounts of iron incorporated into the quartz crystal lattice.
Beyond trace elements, radiation exposure plays a significant role in developing purple hues in some gems, especially amethyst. Natural radiation can alter the electronic state of these iron impurities. This process creates “color centers”—defects in the crystal lattice that selectively absorb certain wavelengths of light.
When white light interacts with these color centers, specific wavelengths, such as green and yellow, are absorbed. The remaining wavelengths, predominantly blue and red, are transmitted or reflected, which our eyes perceive as purple. Similarly, tanzanite’s blue-violet color is due to small amounts of vanadium within its crystalline structure, often enhanced by heat treatment. Purple sapphires derive their color from a combination of chromium, iron, and titanium impurities.
Caring for Your Purple Gems
Proper care maintains the beauty and longevity of purple gemstones. For most purple gems, cleaning with warm, soapy water and a soft brush is a safe and effective method. After cleaning, rinse the gem thoroughly to remove any soap residue and gently pat it dry with a soft cloth.
Avoid ultrasonic and steam cleaners for more delicate purple gems like tanzanite, as these can cause internal damage or fractures due to high-frequency vibrations and heat. Sugilite and amethyst should also not be steam cleaned.
Storing purple gemstones separately in a soft pouch or fabric-lined box prevents them from scratching against harder materials. Protect these gems from prolonged exposure to direct sunlight and extreme heat, as these conditions can cause color fading in some varieties, such as amethyst. Harsh chemicals, including household cleaners, perfumes, and lotions, should also be avoided, as they can damage the gem’s surface or alter its finish.