What is the Difference Between Aquamarine and Blue Topaz

The main difference between aquamarine and blue topaz is that aquamarine is typically a lighter, more pastel blue-green color, while blue topaz can range from a pale blue to a deeper, more saturated blue color.

Aquamarine and blue topaz are two gemstones popular in jewelry making. While they look similar due to their blue color, they are actually two distinct gemstones with different properties and characteristics.

Key Areas Covered

1. What is Aquamarine 
     – Definition, Color, Features
2. What is Blue Topaz
     – Definition, Color, Features
3. Difference Between Aquamarine and Blue Topaz
     – Comparison of Key Differences

Key Terms

Aquamarine, Blue Topaz

What is Aquamarine

Aquamarine is a beautiful gemstone that comes in pale blue to light-green colors. It belongs to the beryl family and has a chemical composition of Be₃Al₂Si₆O₁₈, with some Fe2+ content. It is quite hard, with a range of 7.5 to 8. Although aquamarine has no or few noticeable inclusions, it can contain inclusions like mica, hematite, or salt water. This gemstone is commonly used in jewelry and is named after the color of seawater.

Aquamarine is an affordable gemstone due to its abundance. It is more expensive than blue topaz but less costly than stones like emerald or bixbite. The value of aquamarine depends on its weight, color, cut, and clarity. It’s also the birthstone for March. The gemstone has a historical significance as a symbol of youth and happiness, and its color and name have connected it with the ocean in Western culture. In ancient times, Romans believed that aquamarine could protect travelers who were crossing the sea.

What is Blue Topaz

Blue topaz is a beautiful gemstone that belongs to the topaz family. When found in nature, topaz is usually a very pale blue, making natural blue topaz very rare. However, most blue topaz stones in the market are originally colorless and then treated via heat and irradiation to turn the stone blue. Therefore, while the topaz stone itself is real, its color was artificially added. This process of irradiation is safe and does not affect the durability or stability of the gemstone.

Blue topaz is a hard and durable gemstone, with a hardness of 8 on the Mohs scale, making it ideal for use in jewelry. Blue topaz is available in a variety of shades of blue, from pale sky blue to deep Swiss blue. The most common shades of blue topaz are sky blue, Swiss blue, and London blue. Sky blue topaz is the lightest and most affordable shade, while Swiss blue topaz has a medium to dark blue shade that is more expensive. London blue topaz is the darkest and most expensive shade, with a deep blue hue that almost resembles a sapphire.

Blue topaz is a popular gemstone for use in jewelry because of its beautiful color and affordability. It is also the birthstone for December, making it a popular gift for those born in that month.

Difference Between Aquamarine and Blue Topaz

Definition

Aquamarine is a blue to greenish-blue gemstone that belongs to the beryl family of minerals, while blue topaz is a blue gemstone that belongs to the topaz family.

Composition

Aquamarine is a type of beryl mineral, while blue topaz is a silicate mineral.

Color

While both aquamarine and blue topaz are blue stones, there are some differences in their shades of blue. Aquamarine is typically a lighter, more pastel blue-green color, while blue topaz in the market can range from a pale blue to a deeper, more saturated blue color.

Hardness

While aquamarine has a rating of 7.5 to 8 on the Mohs scale of mineral hardness, blue topaz has a rating of 8.

Inclusions

Aquamarine is generally less likely to have visible flaws, whereas blue topaz may have more visible inclusions due to the irradiation and treatment process.

Rarity

Aquamarine is rarer than blue topaz.

Cost

Aquamarine is more expensive than blue topaz.

Conclusion

Although both aquamarine and blue topaz are gemstones that are blue, there is a difference in their shades of blue. Aquamarine is typically a lighter, more pastel blue-green color, while blue topaz can range from a pale blue to a deeper, more saturated blue color. Thus, this is the main difference between aquamarine and blue topaz.

Reference:

1. “Aquamarine (gem).” Wikipedia. Wikipedia Foundation.
2. “What is Blue Topaz?” Ritani.

Image Courtesy:

1. “Aquamarine crystal” By greyloch (CC BY-SA 2.0) via Flickr
2. “Blue topaz – a” By Mauro Cateb – Own work (CC BY-SA 3.0) via Commons Wikimedia