The Sapphire Series: Everything You Need to Know About Blue Sapphires

Discover everything about blue sapphires: pricing, quality, treatments, origins, and how to choose the perfect stone for your engagement ring.

Blue sapphires are the most ordered, the most desired, and arguably the most essential color in the world of sapphires. In this post, we’ll cover everything from pricing and treatments to origins and quality factors, so you can shop for your engagement ring with confidence.

Shop our sapphires from our curated gemstone collection here

 

What Makes Blue Sapphires So Special?

Sapphires belong to the corundum family, the same mineral group as rubies. With a Mohs hardness of 9, sapphires are second only to diamonds in durability — but unlike diamonds, sapphires lack cleavage planes, making them less prone to cracking. This makes them ideal for everyday wear, especially in engagement rings.

 

How to Evaluate a Blue Sapphire - Color, Clarity and Cut

1. Color

The most important factor when buying a blue sapphire is color. And within that, here’s what you should pay attention to:

• Saturation: The richer the blue, the more valuable the stone. Top-tier colors include “royal blue” and “cornflower blue.” Beware of overly dark stones (often from Australia), which may appear black in low lighting. Dark stones allow less light to pass through, reducing the brilliance of the stone.
  
  

• Color Zoning: This is when parts of the stone appear lighter or show waves of color. It’s common in sapphires and best viewed from the back. What matters most is how clean the stone looks face-up. Color zoning is not necessarily a bad thing, as it can give nuance to the stone. In fact, having no color zoning can make the stone look flat, which is why we often prefer some zoning. The only thing you want to look out for is when it creates large pockets of uneven color.
  
  

• Velvety Look: Some sapphires exhibit a soft, glowing texture known as a velvety appearance. This is found in more saturated stones and adds uniqueness and value.

  Note: Even though the most saturated colors—such as royal blue—are the most valuable due to the rarity of such saturation, we often find clients prefer a slightly paler, medium blue color. A slightly softer shade of blue may be easier to wear. It also has more brilliance, as more light is able to pass through paler colors than darker stones, making them appear more brilliant. They will also be more cost-effective than darker saturations.

  

   

2. Inclusions

Natural sapphires typically contain minor inclusions — they look like tiny needles or crystal dots. All natural sapphires will have some, and it’s a good indicator that a sapphire is natural. However, you do want a stone that is eye-clean. This means that to the naked eye, there are only very minor inclusions, and they are nicely placed — off to the sides of the stone and not on the center table in plain view.

 

3. Cut

Cut significantly impacts a sapphire's sparkle:

• Darker stones require higher-quality cuts, as less light passes through them. This means the top facets must be evenly and precisely cut to ensure maximum brilliance, since the stone is relying mostly on those upper facets due to its more opaque nature
  
  

• Gemstones are not cut in the same way as diamonds, which typically feature a brilliant cut. Instead, gemstones are usually cut using a step-cut. This is why, to the eye, they will always appear slightly different. The reason for this difference is that diamonds and colored gemstones have different refractive indexes and reflect light differently. We generally recommend a hybrid brilliant-step cut, as it offers a good balance of sparkle and depth.
  

  

Natural vs. Synthetic Sapphires

Unlike diamonds, synthetic sapphires are relatively easy to spot. They often lack the depth and nuance found in natural gemstones. Natural sapphires typically display color zoning and inclusions that give them a unique, uneven character, whereas synthetic sapphires tend to appear flat and overly uniform. While they are more budget-friendly, they don’t carry the same value, uniqueness, or individuality as natural stones.

Heated vs. Unheated and Sapphire Treatments: What You Need to Know

Heat Treatment

About 95% of sapphires are heat treated to enhance color and clarity. This is a standard, stable process and doesn’t diminish a stone’s value. Unheated stones, however, command a significant premium.

Diffusion Treatment

This process adds color to the surface by introducing elements like titanium or beryllium. It’s less stable, must be disclosed, and lowers the value of the stone. We do not recommend diffusion-treated stones for engagement rings.

 

Blue Sapphire Buying Guide: What to Expect

Pricing varies dramatically based on color, size, treatment, and clarity. Here's a simplified breakdown :

1 Carat

• Light Blue: $800–$1,000 per carat
  
  

• Medium Blue (Heat Treated): $1,000–$6,000 per carat
  
  

• Royal Blue (Heat Treated): $4,000–$7,000 per carat
  
  

• Royal Blue (Unheated): $5,000–$10,000+ per carat
  
  

2 Carats

• Light Blue: $1,000–$2,000 per carat
  
  

• Medium Blue: $2,000–$8,000 per carat
  
  

• Royal Blue (Heated): $5,000–$8,000 per carat
  
  

• Royal Blue (Unheated): $7,000–$14,000+ per carat
  
  

3+ Carats

Prices rise exponentially with weight:

• Medium Blue (Heated): Up to $25,000
  
  

• Royal Blue (Unheated): $15,000–$20,000 per carat
  
  

Larger, more included stones are more affordable and still provide the "wow" factor.

 

Best Blue Sapphire Origins and Their Influence

The origin of a sapphire can add to its value:

• Kashmir: No longer mined, but stones from this region are known for their soft, velvety look.
  
  

• Sri Lanka (Ceylon): Known for bright, lively blues with great clarity.
  
  

• Madagascar: Now rivals Sri Lanka in quality and size.
  
  

• Thailand & Australia: Often darker, sometimes with more color zoning.
  
  

• Montana (USA): Sought for teal hues; less common in royal blue shades, but still unique.
  
  

Ethical sourcing is possible from places like Sri Lanka, Madagascar, Australia and the US where mining is often community-driven and sustainable.

 

Sapphire Alternatives

If you're drawn to sapphires but want a twist, consider:

Tanzanite

• Deep purplish-blue, often more vivid than sapphire
  
  

• Softer (6–6.5 Mohs), not ideal for daily wear
  
  

• Stunning and more affordable
  
  

Tanzanite’s pleochroism can show both blue and purple hues, depending on how it’s cut and viewed.

 

Final Thoughts

Blue sapphires are not only timeless — they’re versatile, durable, and rich in history. Whether you're choosing a one-carat royal blue sparkler or a bold three-carat unheated gem, there's a sapphire to match every taste and budget.

When buying, remember: Color trumps clarity, heat treatment is normal, and origin adds value. And always work with a trusted jeweler who can provide proper certification and transparency.

 

Want help picking the perfect blue sapphire for your engagement ring? Get in touch — we’d love to guide you through the process.