Why Two 'Blue Sapphires' Can Look Completely Different

You're comparing two sapphires. Both are described as 'blue sapphire.' Both are 2 carats, VS clarity, unheated. One is priced at $3,200. The other at $6,800.

They're both blue—so why the massive price difference?

The answer lies in three factors most buyers don't understand: hue, tone, and saturation. These three elements determine whether a sapphire is a pale, grayish blue worth $1,600/carat or a vivid royal blue worth $3,400/carat.

Gemologists use these terms precisely. Dealers use them loosely (or deceptively). Buyers who don't understand them overpay for mediocre stones or miss exceptional ones.

Here's how to evaluate sapphire color like a professional gemologist—so you know exactly what you're getting and what it's worth.

The Three Dimensions of Color

Hue: What Color Is It?

Definition: The basic color—blue, green, yellow, etc.

Sapphires come in every color except red (red corundum is ruby). The hue describes the primary color and any secondary colors present.

Examples:

• Pure blue: No secondary hues, just blue
• Blue with violet: Primary blue with violet modifier
• Blue-green (teal): Equal or near-equal blue and green
• Green with blue: Primary green with blue modifier

Notation: Gemologists use abbreviations like 'B' (blue), 'vB' (violetish blue), 'bG' (bluish green), 'gY' (greenish yellow)

Tone: How Light or Dark?

Definition: The lightness or darkness of the color, measured on a scale from 0% (colorless) to 100% (black)

Scale:

• 0-20%: Very light (almost colorless)
• 20-40%: Light (pastel)
• 40-60%: Medium (ideal for most sapphires)
• 60-80%: Medium-dark to dark
• 80-100%: Very dark (approaching black)

Optimal tone: 60-75% for blue sapphires (vivid but not too dark)

Saturation: How Pure Is the Color?

Definition: The intensity or purity of the color, from grayish/brownish (low saturation) to vivid/pure (high saturation)

Scale:

• 1-2: Grayish or brownish (very low saturation)
• 3-4: Slightly grayish/brownish (moderate saturation)
• 5-6: Strong to vivid (high saturation, minimal gray/brown)

Optimal saturation: 5-6 (vivid, pure color with no gray or brown modifiers)

How Hue, Tone, and Saturation Work Together

Example 1: Royal Blue Sapphire (Premium)

• Hue: Pure blue (B) or slightly violetish blue (vB)
• Tone: 65-75% (medium-dark)
• Saturation: 5-6 (vivid)
• Description: Deep, rich, saturated blue with no gray or brown
• Value: $2,500-$5,000/carat (unheated)

Example 2: Cornflower Blue Sapphire (Premium)

• Hue: Pure blue (B) or slightly violetish blue (vB)
• Tone: 60-70% (medium)
• Saturation: 6 (vivid)
• Description: Bright, vivid blue like a cornflower, slightly lighter than royal blue
• Value: $3,000-$6,000/carat (unheated, particularly if Kashmir origin)

Example 3: Pale Blue Sapphire (Commercial)

• Hue: Blue (B)
• Tone: 30-45% (light)
• Saturation: 3-4 (moderate)
• Description: Pale, washed-out blue, lacks intensity
• Value: $400-$1,200/carat

Example 4: Grayish Blue Sapphire (Low-Grade)

• Hue: Blue (B)
• Tone: 50-65% (medium)
• Saturation: 2-3 (grayish)
• Description: Blue with significant gray modifier, looks dull and lifeless
• Value: $300-$800/carat

Example 5: Overly Dark Blue Sapphire (Commercial)

• Hue: Blue (B)
• Tone: 80-90% (very dark)
• Saturation: 4-5 (strong but obscured by darkness)
• Description: Almost black, color only visible in bright light
• Value: $500-$1,500/carat

The Sapphire Color Spectrum

Blue Sapphires (The Classic)

Hue range: Pure blue to violetish blue to greenish blue

Most valuable:

• Kashmir blue: Pure blue with slight violet, 60-70% tone, vivid saturation, velvety appearance
• Royal blue: Deep blue, 65-75% tone, vivid saturation
• Cornflower blue: Medium blue, 60-70% tone, vivid saturation

Less valuable:

• Grayish blue (low saturation)
• Overly dark blue (80%+ tone)
• Pale blue (under 50% tone)
• Greenish blue (unless marketed as teal)

Teal Sapphires (The Trending Color)

Hue range: Blue-green (50/50) to greenish blue (60/40) to bluish green (40/60)

Most valuable:

• Balanced blue-green (50/50 to 55/45)
• 60-70% tone (medium)
• Vivid saturation (5-6)

Less valuable:

• Too green (70%+ green)
• Too blue (70%+ blue—just call it blue)
• Grayish or brownish modifiers

Green Sapphires (The Rare One)

Hue range: Pure green to yellowish green to bluish green

Most valuable:

• Pure green or slightly yellowish green
• 60-70% tone
• Vivid saturation

Challenge: Green sapphires often have yellowish or brownish modifiers that reduce value. Pure, vivid green is rare and commands premiums.

Yellow Sapphires (The Sunny Alternative)

Hue range: Pure yellow to orangish yellow to greenish yellow

Most valuable:

• Pure yellow or slightly orangish yellow (golden)
• 60-75% tone (medium to medium-dark)
• Vivid saturation

Less valuable:

• Greenish yellow (common in Australian sapphires)
• Pale yellow (under 50% tone)
• Brownish yellow

Padparadscha Sapphires (The Holy Grail)

Hue range: Pink-orange (50/50 to 60/40 pink-to-orange)

Most valuable:

• Balanced pink and orange (like a lotus flower)
• 60-75% tone
• Vivid saturation
• Unheated

Value: $5,000-$30,000+/carat for natural, unheated stones

Warning: Many 'padparadscha' sapphires are beryllium-diffused (worth 90% less). Demand GIA certification.

Pink Sapphires (The Romantic Choice)

Hue range: Pure pink to purplish pink to orangish pink

Most valuable:

• Pure pink or slightly purplish pink
• 60-75% tone
• Vivid saturation

Less valuable:

• Pale pink (under 50% tone)
• Brownish pink
• Overly purple (approaching purple sapphire)

Australian Sapphire Color Characteristics

Australian Blue Sapphires

Typical characteristics:

• Hue: Pure blue to slightly greenish blue
• Tone: 70-85% (darker than Ceylon or Madagascar blues)
• Saturation: 4-6 (strong to vivid)

Why they're darker: Higher iron content (0.8-1.4%) creates deeper tone

Value consideration: Australian blues compete with Ceylon blues but at lower prices due to darker tone. However, unheated status adds value.

Australian Parti Sapphires

Typical characteristics:

• Hue: Blue-green, blue-yellow, green-yellow combinations
• Tone: 60-75% (medium to medium-dark)
• Saturation: 4-6 (strong to vivid in each color zone)

Unique feature: Sharp color boundaries between zones (unlike gradual color zoning in other origins)

Value driver: Vivid, well-defined color zones with balanced distribution

Australian Teal Sapphires

Typical characteristics:

• Hue: Blue-green (45/55 to 55/45)
• Tone: 60-75% (medium to medium-dark)
• Saturation: 5-6 (vivid)

Why they're valuable: Balanced blue-green hue, vivid saturation, unheated status

Australian Yellow Sapphires

Typical characteristics:

• Hue: Greenish yellow to pure yellow
• Tone: 60-75%
• Saturation: 4-5 (strong)

Challenge: Greenish modifier is common and reduces value compared to pure yellow

How to Describe Sapphire Color Accurately

The Gemologist's Method

Format: [Saturation] [Modifier] [Hue] at [Tone]%

Examples:

• 'Vivid blue at 70% tone' (premium royal blue)
• 'Strong violetish blue at 65% tone' (good quality blue)
• 'Moderate grayish blue at 60% tone' (commercial grade)
• 'Vivid blue-green at 65% tone' (premium teal)

The Dealer's Shorthand (Often Misleading)

Vague terms to watch for:

• 'Royal blue' (could be anything from 60-85% tone)
• 'Cornflower blue' (overused, often inaccurate)
• 'Vivid blue' (doesn't specify tone or modifiers)
• 'Deep blue' (usually means too dark)

Always ask for specific hue, tone, and saturation descriptions.

How to Evaluate Color in Different Lighting

Daylight (The Standard)

Sapphires should be evaluated in natural daylight (not direct sunlight). This reveals true color without artificial enhancement.

Incandescent Light

Blue sapphires often look more purple/violet under incandescent light. This is normal but shouldn't be the primary evaluation condition.

Fluorescent Light

Can make sapphires look slightly different (often cooler/bluer). Not ideal for evaluation.

LED Light

Varies by LED type. Some are close to daylight, others distort color.

Best practice: Evaluate in multiple lighting conditions, but prioritize natural daylight for accurate assessment.

Common Color Grading Mistakes

Mistake #1: Confusing Tone with Saturation

A dark blue sapphire (high tone) isn't necessarily vivid (high saturation). It could be dark and grayish (high tone, low saturation)—which is low-grade.

Mistake #2: Ignoring Modifiers

'Blue sapphire' could be pure blue, grayish blue, greenish blue, or violetish blue. The modifier dramatically affects value.

Mistake #3: Accepting Vague Descriptions

'Beautiful blue' tells you nothing. Demand specific hue, tone, and saturation information.

Mistake #4: Evaluating in Poor Lighting

A sapphire that looks vivid under jewelry store spotlights might look dull in daylight. Always check in natural light.

How to Buy Sapphires Based on Color

Request Detailed Color Descriptions

Ask dealers:

• 'What is the exact hue (pure blue, violetish blue, etc.)?'
• 'What is the tone percentage?'
• 'What is the saturation level?'
• 'Are there any gray or brown modifiers?'

Request Photos in Natural Light

Photos under daylight-balanced lighting show true color. Avoid photos taken only under spotlights or studio lighting.

Request Video

Video shows how color appears as the stone moves and in different angles. More reliable than static photos.

Understand Value Tiers

Premium tier (highest prices):

• Vivid saturation (5-6)
• Optimal tone (60-75% for blues)
• Pure or desirable hue (pure blue, balanced teal, etc.)

Mid-tier (moderate prices):

• Strong saturation (4-5)
• Acceptable tone (55-80%)
• Minor modifiers (slightly grayish, slightly greenish)

Commercial tier (budget prices):

• Moderate saturation (3-4)
• Poor tone (too light or too dark)
• Significant modifiers (grayish, brownish)

The Bottom Line

Two 'blue sapphires' can have completely different values because of hue, tone, and saturation. Understanding these three dimensions lets you:

• Recognize premium color vs commercial color
• Avoid overpaying for mediocre stones
• Identify exceptional stones that are underpriced
• Communicate precisely with dealers
• Make informed decisions based on actual quality, not marketing language

Don't accept vague descriptions like 'beautiful blue' or 'vivid color.' Demand specific information about hue, tone, and saturation—and use that information to evaluate whether the price matches the quality.

Every sapphire in our collection includes detailed color descriptions with hue, tone, and saturation information. We provide photos in natural daylight and video so you can see true color. No vague marketing language—just accurate, gemological color grading.