Which Gemstones Are Hardest?

Gemstones are prized for their beauty and durability, but not all gemstones are created equal when it comes to hardness. The hardness of a gemstone refers to its ability to resist scratching and is measured on the Mohs scale. So, which gemstones are the hardest and most durable? Let's explore.

Understanding Gemstone Hardness

Gemstone hardness is a key factor in determining a gemstone's durability and resistance to scratching. The most commonly used scale to measure gemstone hardness is the Mohs scale, developed by Friedrich Mohs in 1812. This scale ranks gemstones and minerals on a scale of 1 to 10 based on their ability to resist scratching. Diamond, with a hardness of 10, is the hardest gemstone in the world.

Here is a table showcasing the hardness of some popular gemstones according to the Mohs scale:

Gemstone	Mohs Hardness
Diamond	10
Corundum	9
Topaz	8
Quartz	7

Gemstones with a higher ranking on the Mohs scale are more resistant to scratching and therefore more suitable for everyday wear. However, it is important to note that hardness alone does not determine a gemstone's overall durability. Other factors such as toughness and stability also play a significant role.

It is worth mentioning that there are alternative methods to measure gemstone hardness, such as the Vickers Hardness Scale. This scale provides a more precise measurement of hardness by using a diamond to create an indent on the surface of a material. The Vickers scale can be particularly useful for accurately assessing the relative hardness differences between gemstones.

Gemstone toughness and tenacity are important factors to consider when evaluating the durability of gemstones. While hardness measures a gemstone's resistance to scratching, toughness and tenacity assess its ability to withstand breaking and chipping. Brittle gemstones, for example, may be prone to shattering with a hard impact, even if they are highly scratch-resistant.

One such example is diamond, which is renowned for its hardness. However, despite its hardness, diamond is also brittle and can shatter if subjected to a strong blow. On the other hand, gemstones like jade may not be as hard as diamond, but they possess high toughness and can withstand impact without breaking. Jadeite and nephrite, in particular, have very tough tenacity, making them less susceptible to damage from blows.

Understanding the toughness and tenacity of gemstones is vital when selecting jewelry pieces that will withstand everyday wear and tear. It is especially important to consider these factors for gemstones that will be set in rings, as rings are more exposed to potential impacts. By choosing gemstones with high toughness and tenacity, individuals can ensure their jewelry retains its beauty and integrity over time.

Gemstone Toughness and Tenacity Comparison

Gemstone	Toughness	Tenacity
Diamond	Brittle	Brittle
Jade	Very tough	Very tough
Opal	Fair to poor	Brittle

In the comparison table above, we can see that diamond is both brittle in terms of toughness and tenacity. On the other hand, jade exhibits very tough characteristics in both categories. Opal, a gemstone known for its play of colors, is fair to poor in terms of toughness and brittle in terms of tenacity. This highlights the importance of considering both toughness and tenacity when assessing a gemstone's durability.

 

Gemstone Wearability and Durability

When it comes to gemstones, wearability and durability are important factors to consider. Gemstone wearability refers to how well a gemstone can withstand scratches, abrasions, and other forms of wear. On the other hand, durability encompasses a gemstone's overall ability to withstand wear and tear over time. While hardness plays a significant role in wearability, it is not the sole determinant.

For everyday jewelry, gemstones with a hardness of 7 or higher on the Mohs scale are typically recommended. These gemstones include popular choices such as diamonds, sapphires, and rubies. However, it's also important to consider other factors such as stability and toughness. Stability refers to a gemstone's ability to withstand exposure to heat, light, chemicals, and changes in humidity. Some gemstones, like diamonds, are very stable and can resist most forms of deterioration. On the other hand, gemstones like opals and pearls are more sensitive to temperature, chemicals, and moisture.

Toughness, on the other hand, refers to a gemstone's resistance to breaking and chipping. While diamond is very hard, it is also brittle and can shatter with a hard blow. Gemstones like jade, although they may not be as hard as diamonds, have high toughness and can withstand impact without breaking. Tenacity, which measures a material's resistance to blows, is another factor to consider. Most gemstones are considered "brittle," meaning they can break or shatter upon impact. However, there are exceptions like jadeite and nephrite, which have "very tough" tenacity.

Gemstone Wearability and Durability Factors

Gemstone	Hardness (Mohs Scale)	Stability	Toughness
Diamond	10	Very Stable	Brittle
Ruby	9	Stable	Brittle
Sapphire	9	Stable	Brittle
Jade	6.5-7	Stable	Very Tough

As seen in the table above, hardness, stability, and toughness are essential factors in determining a gemstone's wearability and durability. While diamond is the hardest gemstone, it is also brittle. Therefore, gemstones like ruby and sapphire, which are slightly softer but still hard, are popular choices for jewelry. Jade, on the other hand, may not be as hard as diamonds or corundum, but its high toughness makes it suitable for everyday wear.

Gemstone stability is a crucial factor to consider when choosing jewelry. The ability of a gemstone to withstand exposure to heat, light, chemicals, and changes in humidity can significantly impact its durability and longevity. Some gemstones exhibit high stability and can resist most forms of deterioration, while others may be more susceptible to damage.

One example of a gemstone with exceptional stability is diamond, which is known for its resistance to heat and chemicals. Diamond retains its brilliance and strength even when exposed to extreme temperatures and harsh chemical agents. On the other hand, gemstones like opals and pearls are more delicate and can be adversely affected by heat, chemicals, and moisture.

Gemstone Stability Comparison

Gemstone	Stability
Diamond	High
Opal	Low
Pearl	Low

Gemstone Cleavage and Fracture

When assessing the durability of gemstones, it's important to consider their cleavage and fracture properties. Cleavage refers to how easily a gemstone can split along specific planes, while fracture refers to the way a gemstone breaks when subjected to force or impact. These characteristics can significantly impact a gemstone's overall toughness and resistance to breaking.

Diamonds, for example, have perfect cleavage, meaning they can easily split along specific directions. While this property makes them ideal for cutting and shaping, it also makes them more susceptible to chipping or shattering with a hard blow. Other gemstones may have varying levels of cleavage, ranging from perfect to poor. Gemstones with perfect cleavage should be handled and set with caution to minimize the risk of damage.

The fracture properties of a gemstone also influence its breakability. Some gemstones have conchoidal fracture, which means they break with smooth, curved surfaces resembling the inside of a seashell. This type of fracture can be seen in gemstones such as quartz and obsidian. On the other hand, gemstones with uneven or splintery fracture, like fluorite or feldspar, can break into irregular, jagged pieces.

Gemstone	Cleavage	Fracture
Diamond	Perfect	Conchoidal
Quartz	Indistinct	Conchoidal
Obsidian	None	Conchoidal
Fluorite	Perfect	Uneven
Feldspar	Perfect	Uneven

Understanding the cleavage and fracture properties of gemstones can help in selecting appropriate settings and handling techniques to minimize the risk of damage. Gemstones with perfect cleavage should be set with caution and protected from sharp impacts, while gemstones with conchoidal fracture may be more suitable for certain types of jewelry designs.

By considering these factors, individuals can make informed decisions when choosing gemstones that align with their desired level of durability and break resistance.

When it comes to gemstone durability, the type of jewelry setting plays a crucial role in protecting the gemstone from wear and damage. Different gemstones have different levels of hardness, toughness, and stability, and selecting the right setting can help ensure that the gemstone remains intact and beautiful over time.

Rings are particularly susceptible to wear and tear due to their exposure to daily activities. For this reason, it is important to choose a setting that provides adequate protection for the gemstone. Some suitable settings for rings include bezel settings, where the gemstone is surrounded by a metal rim, and V-shaped prong settings, which can securely hold the gemstone in place.

Softer gemstones, such as opals, may be better suited for earrings or pendants, where they are less likely to be subjected to impact or abrasion. In these settings, the gemstones can be securely mounted and displayed without the risk of excessive wear. Additionally, proper prong settings can help protect vulnerable areas of a gemstone, preventing chips and cracks.

Protecting Gemstones with the Right Jewelry Setting

The table below provides a comparison of different jewelry settings and their suitability for protecting gemstones based on their hardness, toughness, and stability:

Jewelry Setting	Suitability for Protecting Gemstones
Bezel Setting	Provides excellent protection for gemstones, especially softer ones, as the metal rim surrounds and secures the gemstone.
V-Shaped Prong Setting	Offers good protection for gemstones, particularly in rings, as the V-shaped prongs securely hold the gemstone in place.
Channel Setting	Offers moderate protection for gemstones, as the gemstones are set within a channel, reducing the risk of exposure to impact and abrasion.
Tension Setting	Provides limited protection for gemstones, as the gemstone is held in place by the tension of the metal, leaving the sides exposed.
Pave Setting	Provides minimal protection for gemstones, as multiple small gemstones are set close together, leaving them more susceptible to damage.

Gemstone Grades and Recommendations

Gemstones are often assigned wearability grades, indicating how suitable they are for different types of jewelry and wear. These grades take into account factors such as hardness, toughness, and stability, providing valuable insights for selecting durable gemstones.

Here is a breakdown of the wearability grades commonly used:

Grade	Description
Excellent	Gemstones with excellent wearability can be worn in any setting and for any occasion. They are highly durable and resistant to scratches, abrasions, and other forms of wear.
Very Good	Gemstones with very good wearability are also highly durable and suitable for everyday wear. They may have slight vulnerabilities to certain types of wear and tear, but overall, they maintain their beauty and integrity well.
Good	Gemstones with good wearability are durable and can withstand normal wear and tear. However, they may require some extra care to avoid damage from certain activities or conditions.
Fair	Gemstones with fair wearability have moderate durability and may show signs of wear more quickly than higher-grade gemstones. They require careful handling and occasional maintenance to preserve their appearance.
Poor	Gemstones with poor wearability have lower durability and may not be suitable for everyday wear. They may require special care or limited use to avoid damage.
Display Only	Gemstones with the display-only grade are highly delicate and require utmost care. They are not recommended for regular wear and are better suited for display purposes.

It's important to consider a gemstone's wearability grade when selecting jewelry. Depending on your lifestyle and preference, you can choose gemstones that offer the desired balance between durability and aesthetic appeal.

The Influence of Gemstone Treatments

Gemstone treatments are commonly used in the industry to enhance the appearance, color, and clarity of gemstones. These treatments can significantly impact a gemstone's durability and stability, making it important for consumers to understand the effects and potential risks involved. It is crucial to consider the treatments a gemstone has undergone when assessing its overall durability and care requirements.

Some treatments, such as coating and fracture filling, may not be permanent and can be damaged by exposure to heat or certain chemicals. These treatments can affect the stability of a gemstone, potentially leading to color changes, fading, or even the complete deterioration of the treated area. It is essential to handle treated gemstones with care and avoid exposing them to harsh conditions that could compromise their longevity.

However, not all gemstone treatments have negative effects on durability. Certain treatments, such as heat treatment or irradiation, can enhance a gemstone's color or clarity without significantly impacting its stability. These treatments are often considered industry-standard and can provide beautiful, durable gemstones that are suitable for everyday wear. It is important to consult with reputable jewelers or gemologists to ensure the treatments applied to a gemstone are of high quality and will not compromise its durability.

Treatment Type	Effect on Durability
Coating	May not be permanent, can be damaged by heat or certain chemicals
Fracture Filling	May not be permanent, can be damaged by heat or certain chemicals
Heat Treatment	Enhances color or clarity, minimal impact on durability
Irradiation	Enhances color or clarity, minimal impact on durability

It is always advisable to ask for documentation or certification that details any treatments a gemstone has undergone. This information can help you make an informed decision about the durability, care, and longevity of the gemstone. By understanding the influence of gemstone treatments on durability, you can confidently select gemstones that will withstand daily wear and maintain their beauty for years to come.

While the Mohs scale is commonly used to measure gemstone hardness, there is another method called the Vickers Hardness Scale that provides a more precise measurement. The Vickers scale involves using a diamond to create an indent on the surface of a material and then measuring the size of the indent. This scale can reveal the relative hardness differences between gemstones and provide valuable information for selecting durable gemstones.

Unlike the Mohs scale, which gives a relative ranking of gemstone hardness, the Vickers scale provides a numerical value that represents the hardness of a gemstone. This scale is widely used in the jewelry industry and is especially useful when comparing gemstones that have similar rankings on the Mohs scale.

Gemstone Hardness Testing using the Vickers Scale

To determine a gemstone's hardness using the Vickers scale, a qualified gemologist or jeweler will use a Vickers hardness tester. This device applies a controlled pressure to the surface of the gemstone using a diamond indenter, creating a small indent. The size of the indent is then measured under a microscope, and the hardness value is calculated based on the applied pressure and the area of the indent.

It's important to note that gemstone hardness testing using the Vickers scale is a specialized process that requires expertise and proper equipment. Therefore, it is typically performed by professionals in a gemological laboratory or a reputable jewelry store. By using the Vickers scale, jewelers and gemologists can accurately assess the hardness of gemstones and provide valuable information to customers when selecting durable jewelry pieces.

Gemstone	Mohs Scale	Vickers Scale
Diamond	10	10000
Corundum	9	2200
Topaz	8	1100
Quartz	7	820

This table illustrates the comparison between gemstone rankings on the Mohs scale and their corresponding hardness values on the Vickers scale. As shown, diamond, with a Mohs hardness of 10, has a Vickers hardness of 10000, making it the hardest gemstone. Corundum, topaz, and quartz, with lower rankings on the Mohs scale, also have lower hardness values on the Vickers scale.

By considering both the Mohs scale and the Vickers scale, individuals can make well-informed decisions when selecting gemstones for jewelry, ensuring they choose durable and long-lasting pieces that will withstand everyday wear and maintain their beauty over time.

Conclusion

When picking out gemstones for jewelry, durability matters. We know diamond is the hardest substance, but that alone doesn’t determine how well a gem withstands daily wear. Toughness, measuring resistance to chipping, also plays a role. Stability indicates if a stone can handle changes in temperature or chemicals without damage. And wearability depends partly on hardness - it signifies how easily scratches might form.

By weighing all these durability factors - toughness, stability, wearability and the setting style - you can select gems that dazzle for years. An “Excellent” grade sapphire could handle any occasion. But for earrings, opt for highly stable gems, as they encounter more exposure.

Do your homework before you shop, considering how different stones hold up. Choose pieces with enduring sparkle by picking durable gems in settings they can thrive in.