Emeralds, with their striking green hues, have captivated humanity for centuries. A common question arises when considering these beautiful gems: are emeralds hard or soft? Understanding their durability is important for anyone admiring or owning these precious stones.
What Gemstone Hardness Means
In the context of gemstones, “hardness” refers to a material’s resistance to scratching. It does not measure a gem’s resistance to breaking or chipping. The most widely recognized system for measuring this property is the Mohs Scale of Mineral Hardness.
The Mohs scale ranges from 1 (softest) to 10 (hardest). Each number represents a reference mineral that can scratch any mineral with a lower rating and, in turn, can be scratched by any mineral with a higher rating. For example, talc is at 1, while diamond is at 10. This scale helps jewelers and consumers understand how well a gemstone might resist scratches from everyday wear.
Emerald’s Place on the Hardness Scale
Emeralds rank between 7.5 and 8 on the Mohs scale. This rating indicates good resistance to scratching from common household dust, which often contains quartz (Mohs 7). An emerald is harder than many everyday materials, but it is not as hard as corundum (sapphires and rubies, Mohs 9) or diamond (Mohs 10).
Emeralds are a variety of the mineral beryl. Their distinctive green color comes from trace amounts of chromium, vanadium, and sometimes iron. While their Mohs hardness is high, emeralds frequently contain natural internal fissures and inclusions, often referred to as “jardin.” These internal characteristics can make emeralds more susceptible to chipping or breakage upon impact compared to gemstones with fewer inclusions.
Ensuring Your Emerald’s Longevity
Despite their respectable hardness, emeralds require specific care to maintain their beauty. The presence of natural inclusions means they can be more fragile than their Mohs hardness might suggest, making them vulnerable to sudden impacts or extreme temperature changes. It is advisable to remove emerald jewelry during activities that might expose it to harsh bumps, such as sports or household chores.
Cleaning emeralds should always be done gently using mild soap and lukewarm water. A soft cloth or brush can be used to wipe away dirt, but vigorous scrubbing should be avoided. Many emeralds undergo oil or resin treatments to enhance their clarity, and harsh chemicals, ultrasonic cleaners, or steam cleaners can strip these treatments, potentially affecting the gem’s appearance and stability. When storing emerald jewelry, keep pieces separate in a soft pouch or a dedicated compartment within a jewelry box to prevent scratches from harder gems. Regular professional inspection for loose settings can also help ensure the longevity of these beautiful gemstones.