Blue Topaz vs Blue Zircon – The Similarities and Differences (With Photos)

By Dr. Keith Jackson - Geology PhD

| Updated

Blue Topaz vs Blue Zircon – The Similarities and Differences (With Photos)

By Dr. Keith Jackson - Geology PhD


Blue zircon and blue topaz are two cool gems that often get mixed up because they both can be the color of the ocean. To compare blue zircon vs blue topaz, it’s fun to look at what sets them apart and what they share.

Blue zircon shines really bright because it has something called high dispersion, making it sparkle with lots of colors. Blue topaz, on the other hand, is known for being super clear and coming in different shades of blue.

Both stones are admired for their unique characteristics that set them apart from other gems. They’re special in their own right, offering a variety of options for those interested in their beauty.

Blue Zircon vs Blue Topaz – The Major Differences

Let’s look into how blue zircon and blue topaz are different from each other. Even though they both look really pretty in blue, there are some cool things that set them apart.

Luster – Blue zircon sparkles a bit like diamonds.

oval cut sky blue zircon
Blue zircon provided by MilleniumEarthGems

Luster is how light bounces off the surface of a gem, making it look shiny or dull. Blue zircon has a very high luster, so it reflects light really well, almost sparkling like a diamond.

Blue topaz also shines, but its luster isn’t as intense as blue zircon’s. This means while blue topaz looks pretty and shiny, it doesn’t catch the light in quite the same eye-catching way.

Because of this difference in luster, blue zircon can look more brilliant and fiery, especially under the sun. Blue topaz, though still beautiful, has a softer glow that gives it a more subtle appeal.

Clarity – Blue topaz tends to be naturally clear and free of inclusions.

rectangular sky blue topaz
Blue topaz provided by GarnetCity

Clarity is about how clear a gemstone is, meaning it doesn’t have any marks or bits inside it that you can see.

Blue zircon is usually very clear, but sometimes, it might have small marks or inclusions that you can see if you look closely, especially if the stone hasn’t been treated.

Blue topaz, on the other hand, is naturally super clear. Most of the time, you won’t find any visible marks or inclusions inside it.

Hardness – Blue zircon is softer and can get more easily scratched.

rough blue zircon
Blue zircon provided by Freakenfru

The Mohs hardness scale is a way to measure how tough and scratch-resistant a gemstone is. It goes from 1 to 10, where 10 is the hardest, like a diamond.

Blue zircon lands between 6 and 7.5 on this scale, showing it’s pretty tough but can get chipped if it’s hit hard.

Blue topaz scores an 8 on the Mohs scale, which means it’s harder and more scratch-resistant than blue zircon. This makes blue topaz a great choice for everyday jewelry since it can stand up to more bumps and scratches.

Crystal Structure – Blue topaz grows in column-like crystals.

raw pale blue topaz crystal
Blue topaz provided by HealingCrystalShopCA

Crystal structure is basically how the tiny pieces that make up a gemstone fit together. To differentiate blue zircon vs blue topaz, you can look at their crystal structures, which are like the building plans for each stone. 

Blue zircon has a tetragonal crystal system, which means its crystals form in shapes that are kind of like stretched cubes. This gives blue zircon gems a unique look, especially when they catch the light. 

Blue topaz crystals grow in the orthorhombic system, making their shapes different from zircon’s. They have longer, and sometimes column-like, crystals that create the base for their beautiful gem forms.

Cleavage – Blue zircon has a conchoidal fracture.

raw blue zircon crystal
Blue zircon provided by Freakenfru

Cleavage is how a gemstone can split along specific lines based on its crystal structure. It’s like how wood splits easier in one direction than another.

Blue zircon has what’s called indistinct cleavage, which means it doesn’t split easily along a flat plane. Instead, it has a curved breakage that looks like the inside of a shell.

Blue topaz, however, has perfect cleavage in one direction. This means it can be split very cleanly along one line. When cutting blue topaz, gem cutters have to be really careful not to hit it the wrong way, or it could split apart.

Chemical Composition – Blue topaz contains aluminum and fluorine.

rough pale blue translucent topaz crystal
Blue topaz provided by RocksNFound

Chemical composition is like a recipe that tells us what a gemstone is made of. Blue zircon is made of zirconium silicate, which is a mix of zirconium and silicon atoms.

This recipe makes blue zircon unique, and its blue color usually comes from being heated up.

Blue topaz has a different recipe. It’s made of a silicate mineral that includes aluminum and fluorine. While blue topaz can be found in nature, it’s also super rare. So, most of the time, topaz stones are also heated to bring out a blue color.

Density – Blue zircon feels heavier.

round cut bright blue zircon
Blue zircon provided by NikiDiamondGems

Density is basically how much stuff is packed into a certain amount of space. Blue zircon is pretty dense, which means it has a lot of material crammed into it, making it feel heavier than you might expect when you pick it up.

Blue topaz, on the other hand, isn’t packed as tightly, so it’s not as heavy. If you held a blue topaz and a blue zircon of the same size in each hand, the blue zircon would feel heavier.

Formation – Blue topaz forms in pegmatite rocks.

rough pale blue topaz crystal with brown inclusions
Blue topaz provided by Zensnapple

Blue zircon is made deep inside the Earth, where it gets really hot. It forms from cooling magma, which is melted rock, and turns into beautiful crystals as it cools down and hardens.

Blue topaz forms in a different way. It grows in places where there are lots of minerals and very high heat, like in pegmatite rocks or places with lots of quartz. This makes it a bit rare and very special.

For the best rockhounding locations, you’ll want to look in areas known for their igneous rocks for zircon and pegmatite or quartz-rich spots for topaz. These kinds of terrains are where you might find these awesome gems.

Fluorescence – Blue zircon glows a bright yellow under ultraviolet light.

emerald cut teal blue zircon
Blue zircon provided by GemsByGemstore24

Fluorescence is when a gemstone glows under ultraviolet light, kind of like how some posters light up under a blacklight.

Blue zircon is pretty cool because it can glow a mustard yellow to yellow-orange color when you shine UV light on it.

Blue topaz reacts a bit differently under UV light. It might not glow as much, and if it does, it usually lights up with a yellow or greenish color, but it’s often much weaker than blue zircon’s glow.

Price – Blue topaz is relatively less expensive.

octagonal deep blue topaz
Blue topaz provided by SBIGems

The price or value of gemstones depends on things like how rare they are, how pretty they look, and how hard they are to find or make. Blue zircon is pretty, but it’s more common than some other gems, which usually makes it more affordable.

Blue topaz is also not too expensive, especially the kinds that have been treated to show off their blue color better. Compared to blue zircon, blue topaz is often less pricey, making it a popular choice for jewelry.

If you’re curious about how much you might spend on blue gems, our guide on the price of topaz is a good place to start.

Location – Blue zircon can be found in Cambodia.

several rough blue zircon crystals
Blue zircon provided by GenuineGemsStone

Blue zircon comes from some pretty interesting places around the world. Countries like Cambodia, Sri Lanka, and Vietnam are known for digging up some of the most beautiful blue zircons you can find.

Blue topaz is found in a bunch of different spots too. Places like Brazil, Nigeria, and even the USA have mines where people find blue topaz in various shades of blue, from light to dark.

Our guide to finding gems near you can help you learn more about where to look. It talks about the locations where zircon and topaz can be found.

Blue Topaz vs Blue Zircon – The Similarities

Blue zircon and blue topaz look a lot alike with their cool blue hues, but they have more similarities if you delve deeper. We’re going to explore the common ground between these two gems.

Colors – Blue topaz and blue zircon have a similar range of hues.

faceted deep blue topaz
Blue topaz provided by TheGemsGalleria

Both blue zircon and blue topaz show off a beautiful range of blues, from light sky colors to deep ocean hues. This makes them both really popular for people who love the color blue in their jewelry.

Sometimes, both of these gems can have a hint of green or teal, making them look even more like the sea. This similarity can make it tricky to spot the difference between blue zircon and blue topaz just by looking at their colors.

The deep blue stones known as London blue topaz are especially similar to some shades of blue zircon. Both gems can catch the eye with their rich, vibrant blue tones, making them favorites for all kinds of accessories.

Magnetism – Neither gem is magnetic.

oval cut sky blue zircon
Blue zircon provided by GemsByGemstore24

Magnetism is when a material can be attracted by a magnet. It’s like how fridge magnets stick to the fridge. Blue zircon doesn’t stick to magnets at all, which means it’s not magnetic.

Blue topaz is the same way; it doesn’t show any magnetism either. So if you try to stick a magnet to either of these gems, nothing will happen.

Streak – Both gems leave a white streak.

rough pale blue topaz crystal
Blue topaz provided by HealingCrystalShopCA

Streak is the color of the powder a gem leaves behind when it’s scratched across a special plate, usually made of porcelain. Both blue zircon and blue topaz have a white streak, which means they leave a white powder when tested this way.

This white streak is one of the cool things they have in common. It’s a handy detail for scientists and gem lovers to know because it helps identify the gems.

Conductivity – Blue zircon cannot conduct electricity, and neither can blue topaz.

cushion cut light blue zircon
Blue zircon provided by PreciousLaceGems

Conductivity is about whether something can let electricity flow through it. Metals are usually really good at this, but not all materials can do it.

Blue zircon can’t conduct electricity, which means if you tried to pass an electric current through it, nothing would happen.

Blue topaz is also not good at letting electricity flow through it. Just like blue zircon, it’s an insulator, which means it keeps electricity from moving through it.

The Easiest Ways to Tell Blue Zircon and Blue Topaz Apart

There are some cool tricks to tell blue zircon and blue topaz apart, even though they look a lot alike. We’re going to check out how you can spot the differences between these two blue gems.

Evaluate the Weight

emerald cut deep blue topaz
Deep blue provided by RajwadaGems

When you pick up a gemstone, you can tell a lot by how heavy it feels in your hand. Blue zircon is denser, which means it feels heavier than a blue topaz of the same size.

This trick is really handy when trying to figure out blue topaz vs blue zircon without any fancy tools. Just by holding them, you can get a sense of which is which based on their weight.

So, if you’re holding two stones and one feels noticeably heavier, it’s likely the blue zircon. The lighter one, on the other hand, would probably be the blue topaz, making it easier to tell them apart.

Examine the Dispersion

oval cut bright blue zircon
Blue zircon provided by gemox

When you shine a light on blue zircon, it’s like watching a mini-fireworks show inside the stone. This happens because blue zircon has high dispersion, which makes light split up into all colors of the rainbow as it passes through.

Blue topaz also shines under the light, but it doesn’t break the light into as many colors. This means you won’t see the same kind of colorful sparkle in blue topaz that you do in blue zircon.

Besides the colorful sparkles, blue zircon has a super shiny surface that makes it look almost like a diamond. Blue topaz is shiny too, but its shine doesn’t quite reach the dazzling levels of blue zircon.

Examine Under UV Light for Fluorescence

cushion cut bright blue topaz
Blue topaz provided by farangems

When you use a UV light on blue zircon, it’s like turning on a light bulb because it glows with a bright yellow-green color. This cool trick makes blue zircon stand out, especially in the dark.

Blue topaz, on the other hand, doesn’t really have this glow-up moment under UV light. If it does glow, it’s super faint, so you might not notice it much, which is a big clue when you’re trying to figure out what gem you have.

So, shining a UV light on these gems can help you see the difference between them. The one that lights up bright yellow-green is probably the blue zircon, while the one that doesn’t glow as much, or at all, is likely the blue topaz.

About Dr. Keith Jackson - Geology PhD

Keith Jackson is an avid rockhound who is constantly exploring new sites to expand his collection. He has worked as a professional Geologist for over 20 years and holds a PhD in Geology from the University of Nebraska-Lincoln, a Masters Degree in Geology from the University of Nebraska-Lincoln, and a Bachelors Degree in Geology from the University of Connecticut.

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