Sapphire VS Topaz – Discussing These Two Blue Stones

Sapphire and topaz are two common gemstones you’ll find in many jewelry pieces, and both have their unique beauty. Sapphires are renowned for their deep, rich blue hues while topaz is known as a lighter color stone, sometimes found as a shade of blue.

What are the main differences between sapphire and topaz ? Could you use topaz instead of sapphire in some cases ? How can you tell which you’ve got ? Read on to find out more.

sapphire topaz

Sapphire vs topaz

Sapphires have a deeper, more vivid shade of blue than topaz, and they are also a harder gemstone than topaz, making them more scratch-resistant. Because of this sapphires are far more expensive than topaz, and also much rarer.

Sapphire is a type of corundum, topaz is silicate

Sapphires are a type of corundum, which is aluminum dioxide. It’s a strong mineral and it shares the aluminum part with topaz. Topaz is silica mixed with aluminum and fluorine, and like all silica-based minerals it’s a bit brittle.

Topaz is a softer stone than sapphire

Because sapphire is actually corundum, it’s harder than topaz. Sapphire ranks a 9 on the Mohs hardness scale while topaz ranks an 8. This means that sapphire can withstand scratches and will stand the test of time better than topaz.

Generally gemstones over 7 are fine to wear everyday, but a topaz will show small scratches in time, leading to less shine. for this reason it’s best to use them as occasional rings, or earrings, or pendants. This way they are less subject to scratching.

Read also: Brilliant Cut VS Step Cut 

Blue topaz is much rarer in nature than blue sapphire

Topaz comes in many colors, not only blue. In fact blue topaz is the rarest topaz in nature, while blue sapphire is the most common form of sapphire. The perfect sapphire color is a deep, dark cornflower blue with no other color flashes. Lower quality specimens may have slight green tinges.

The blue coloring in sapphire comes from trace amounts or iron and titanium, and its color is a perfect deep blue. However nearly all sapphires are heat-treated to reach this beautiful color, as natural sapphires come in varying shades of blue and are less impressive.

Blue topaz is very rare in nature, and most of the specimens you see for sale are other colors (like yellow) that have been irradiated to get to a blue color. When blue, topaz is more of a sky or baby blue than a deep blue like sapphire.

A word on London blue topaz

There is a type of blue topaz that is a very dark blue (for a topaz). This is the London blue topaz, and no one is sure why or how it got its name. The point is that this topaz color, even as a darker blue, is not as blue as a sapphire.

Where sapphires have an indigo sort of blue, topaz always has a sea blue kind of color, even in its darkest version. It always has a slight green hue, especially when compared to sapphire.

Sapphire is more expensive than topaz

Sapphires are always going to be more expensive than topaz, simply because they are a very hard and rare material, and their color is simply more impressive. For example you can expect to pay around $70 for 3-3.5 ct blue topaz, and a whopping $8,382 for 3-3.5 ct blue sapphire.

The way a sapphire is priced is mostly according to color, and then clarity. A perfect color with reasonable clarity is worth more than a perfectly clear yet poorly colored sapphire.

Topaz is always going to be a clear stone, so you don’t have to worry about that, and it too ranks color above other elements. The trouble is that topaz doesn’t reach a very vivid color in general.

Topaz may fade in sunlight, sapphire does not

Topaz is a much more sensitive gemstone than sapphire, especially when it comes to retaining its color. This gemstone may fade if kept in direct sunlight for long periods of time. This does not mean you can never wear topaz jewelry outside, but it does mean you should be careful to not wear it too often if you live in an especially sunny area.

Sapphire on the other hand does not have this problem, and can take a good amount of sun without changing its color in time.

Can you use topaz instead of sapphire ?

No, we don’t recommend using topaz instead of sapphire because you’re getting two very different shades of blue, and different gemstones in terms of hardness. This will become apparent in time as the topaz wears down faster than the sapphire.

What is the most valuable topaz ?

The most valuable topaz is the Imperial topaz, and it ranges from an amber color to orange-pink to true pink, with pink being the most rare and expensive color. This kind of topaz can reach anywhere between $1000 – $3.500 per carat, depending on the quality of them gem.

What is the most valuable sapphire ?

The most valuable sapphire is the Blue Belle of Asia, a very large and perfectly blue sapphire from Ceylon. It’s a 392.52 carat gem, and it sold for $17,564,156 in 2014. That’s $44,747 per carat !

In general the blue sapphires coming from Ceylon, Burma, and Kashmir are viewed as extremely desirable due to their high quality and very good pigmentation. These sapphires generally have exquisite color.