Sapphires
Sapphires
Ceylon sapphires are among the world’s most admired corundum, valued for their purity, brilliance and exceptional colour stability. Sri Lanka is known for producing stones with vivid saturation, high clarity and strong light performance, making them ideal for fine jewellery and investment-grade selections.
Gemmological Characteristics
- Mineral species
Corundum (Al₂O₃) - Colour range
Cornflower blue, royal blue, pastel to saturated tones, typical of Sri Lanka. - Hardness
Mohs 9 — extremely resistant and suitable for daily wear. - Refractive Index
Approx. 1.760–1.770 (high brilliance and light return). - Birefringence
0.008–0.010 — contributes to the stone’s visual depth. - Crystal system
Trigonal, responsible for natural pleochroism. - Specific Gravity
Approx. 3.95–4.03. - Pleochroism
Blue, greenish-blue, or violet-blue depending on viewing angle. - Typical inclusions
Rutile silk, growth lines, fingerprint inclusions, crystal needles. - Optical phenomena
Asterism (star sapphires) in stones containing aligned rutile. - Common treatments
Heat treatment is common and accepted; unheated stones are rare and highly prized.
Value Factors
- Colour Quality (Most important factor)
Highest value for:
• Cornflower blue (bright, airy, luminous)
• Royal blue (deep, rich, vivid)
• Even and stable colour without grey or green tones - Clarity
• Eye-clean stones increase significantly in value
• Fine silk can enhance the velvety appearance in elite sapphires - Cut Quality
• Maximises brilliance, symmetry, and saturation
• Preferred shapes: oval, cushion, round
• Precision cutting greatly influences final price - Carat Weight
• Price increases sharply above 3 ct
• Fine stones over 5 ct are rare and considered investment-grade - Origin
Origins with the strongest market appeal:
• Sri Lanka (Ceylon): exceptional brightness and clarity
• Kashmir: velvety blue, extremely rare, top collectible value
• Madagascar: modern source of vivid, high-quality blues - Treatments
• Unheated sapphires: significant premium
• Heat-only: industry standard and stable - Certification
Value increases with certificates from:
GIA, IGI, SSEF, GRS
Blue sapphire
- Blue sapphires are the timeless icons of the corundum family, celebrated for their depth, purity, and exceptional luminosity. Though corundum is naturally colourless, the blue hue arises when trace amounts of iron (Fe) and titanium (Ti) enter the crystal structure during formation. These elements interact with light through a process known as charge transfer, selectively absorbing certain wavelengths and reflecting the rich spectrum of blues—from soft cornflower to intense royal tones.
- The intensity and purity of colour depend on several natural factors:
• the geological environment in which the crystal grows (temperature, pressure, mineral composition);
• the concentration and balance of iron and titanium;
• the structural perfection of the crystal, as fewer inclusions enhance clarity and brightness. - This unique interplay of chemistry, geology, and time creates sapphires whose colour remains remarkably stable under any lighting. Sri Lankan blue sapphires, in particular, are renowned for their exceptional clarity and vibrant inner glow—qualities that make them some of the most sought-after gems in the world.
- With a hardness second only to diamond, blue sapphires are ideal for fine jewellery meant to endure for generations. Choosing one means selecting a gemstone that represents prestige, refinement, and the enduring beauty of nature’s craftsmanship.
Pink Sapphire
Pink sapphires owe their enchanting colour to tiny traces of chromium within the corundum crystal structure. When chromium replaces part of the aluminium atoms, it selectively absorbs certain wavelengths of light and reflects others, producing the gem’s characteristic pink tones—ranging from soft pastel rose to vivid fuchsia.
The intensity of colour depends entirely on the concentration of chromium present:
• lower levels create delicate, light pink shades;
• higher levels produce vivid pinks that, at their strongest, shift into ruby red.
This remarkable range of hues is shaped by the stone’s geological environment, the distribution of trace elements, and the unique conditions under which it formed. Each pink sapphire is, therefore, a one-of-a-kind natural creation—part of what makes these gems so cherished in fine jewellery and bespoke designs.
Yellow Sapphire
Yellow sapphires are admired for their radiant, sun-lit brilliance, displaying a spectrum that ranges from delicate lemon tones to rich golden amber. Their colour is created by the presence of iron within the corundum crystal lattice: this element selectively absorbs certain wavelengths of light, allowing warm, luminous yellow reflections to dominate. The result is a gemstone whose glow remains remarkably stable under all lighting conditions.
Ceylon yellow sapphires are especially valued for their exceptional clarity and natural brightness, qualities that give them an unmistakable vitality. Their strong symbolism—often associated with prosperity and well-being—combined with outstanding durability, makes them ideal centrepieces for refined and enduring jewellery.
Star Sapphire
Star sapphires possess a mystical charm, distinguished by their captivating asterism: a luminous six-rayed star that glides across the surface when exposed to light. This enchanting optical effect is caused by fine rutile inclusions aligned within the crystal during its natural formation.
Sri Lankan star sapphires are treasured for their depth, character, and unique personality—no two are ever the same. Their velvety body colour, combined with the hypnotic movement of the star, makes them highly desirable collector’s stones and icons of timeless fascination.
- The yellow colour of sapphires is caused by the presence of trace elements within the crystal structure of corundum (aluminium oxide).
In yellow sapphires, the key element responsible is iron (Fe³⁺): - When iron is present in specific concentrations, it absorbs part of the visible light spectrum.
- It mainly absorbs blue and violet wavelengths.
- The remaining light, especially yellow, is reflected back to the eye.
- This creates a colour range that can vary from soft pastel yellow to deep golden tones, highly valued in fine gemology.
- Yellow sapphires are renowned for their brightness, brilliance, and exceptional colour stability—their hue remains consistent in different lighting conditions, making them ideal for high-end jewellery.
Teal Sapphire
Teal sapphires stand out for their refined blend of blue and green tones—an elegant fusion inspired by the depth of the ocean and the serenity of natural landscapes. Created by a unique combination of iron and titanium, these stones offer a modern aesthetic with remarkable individuality.
Highly sought after for their contemporary appeal, Sri Lankan teal sapphires exhibit excellent clarity and a balanced, harmonious colour palette, making them coveted by designers and collectors seeking rare, expressive gemstones.
Teal sapphires display a rare balance of blue and green tones, created by the presence of two key elements:
- Iron (Fe) for green
- Titanium (Ti) for blue
When these elements occur together in the right proportions, they produce the distinctive blue-green fusion that defines teal sapphires—ranging from deep ocean hues to modern, cool tones. These gems are highly prized for their natural beauty and contemporary character.
White Sapphire
White sapphires embody purity, luminosity, and refined simplicity. Free from the trace elements that produce colour in other varieties of corundum, they allow light to pass through with exceptional clarity, resulting in a naturally bright and radiant appearance.
Because they contain no significant amounts of iron, titanium, chromium, or other colour-inducing elements, their beauty lies in the true, pristine essence of corundum itself. This purity gives them a crystalline brilliance that offers an elegant alternative to other colourless gemstones.
- Their durability and timeless aesthetic make white sapphires ideal for minimalistic yet luxurious jewellery—perfect for those seeking sophistication, brilliance, and authenticity in its most natural form.
RUBY
DESCRIPTION
Rubies are the red variety of corundum, admired for their intensity, brilliance, and remarkable range of tones. The most prized is the Pigeon Blood ruby, celebrated for its vivid, highly saturated red enhanced by a natural fluorescence that makes the gem appear to glow from within.
Equally sought after are vivid red rubies with rich saturation and brightness, as well as pinkish-red stones whose lighter tones can border those of fine pink sapphires. Another fascinating category is the star ruby, which exhibits a six-rayed star caused by fine rutile inclusions—an optical effect known as asterism.
Although many rubies are completely natural, some undergo heat treatment or filling to enhance clarity and colour—standard and accepted practices in the gemstone industry.
The ruby’s iconic red hue is produced by trace amounts of chromium within otherwise colourless corundum. When chromium replaces part of the aluminium in the crystal lattice, it absorbs green wavelengths and reflects red ones, creating the gem’s characteristic colour and contributing to its natural fluorescence, especially in sunlight.
Variations in shade and intensity among rubies are influenced by chromium concentration, the presence of iron, natural inclusions, geographic origin, and any treatments performed on the stone.
Characteristics
- • Mineral species: Corundum
• Composition: Aluminium oxide with chromium
• Colour range: Pinkish red → vivid red → deep red (including Pigeon Blood)
• Optical effects: Possible asterism (star ruby) due to rutile inclusions
• Fluorescence: Often strong red under UV or sunlight
• Clarity features: Natural inclusions common (silk, crystals, needles)
• Treatments: Heat treatment common; fracture filling occasionally seen
• Hardness: 9 on the Mohs scale (exceptionally durable)
• Origin influence: Tone and fluorescence affected by chromium/iron balance
• Formation factors: Chromium levels, presence of iron, geological environment
Value Factors
- • Colour:
– The most important factor: vivid, saturated red is the highest grade
– Pigeon Blood commands the strongest market prices - • Clarity:
– Eye-clean rubies are rare
– Fine inclusions that cause asterism increase value for star rubies - • Cut quality:
– Enhances brightness and depth of colour
– Well-proportioned stones carry higher value - • Carat weight:
– Rubies increase exponentially in value with size
– High-quality stones above 2–3 ct are exceptionally rare - • Origin:
– Burmese (Myanmar) rubies typically command premium prices
– Sri Lankan, Mozambique, Vietnam and Tanzania produce highly valued stones - • Treatment status:
– Untreated rubies hold the highest value
– Heated stones have moderate to high value depending on colour
– Filled or heavily treated stones are significantly less val
MOONSTONE
DESCRIPTION
Moonstone is a captivating gemstone celebrated for its soft, ethereal glow known as adularescence—a shimmering light that appears to float just beneath the surface of the stone. This luminous effect is created by the gem’s internal structure: thin, alternating layers of feldspar that scatter incoming light and produce the gentle radiance reminiscent of moonlight.
The finest moonstones display a clear, silvery-blue sheen that moves gracefully across the gem when it is rotated. Sri Lanka is renowned for producing some of the world’s highest-quality specimens, prized for their clarity and strong blue adularescence.
Moonstone occurs in various natural shades, including colourless or white with a blue sheen, soft peach, champagne, grey, and brown. The popular rainbow moonstone—technically a variety of labradorite—exhibits vibrant multicoloured flashes ranging from blue to gold to violet, making it especially desirable in contemporary jewellery.
The beauty of moonstone depends on the thickness, spacing, and regularity of its internal layers: the more refined these structures, the stronger and more captivating the adularescence. Natural inclusions, mineral composition, and geographic origin also influence the gem’s appearance, giving each moonstone its own distinct personality and timeless charm.
Characteristics
- • Colour Range: colourless, white, blue sheen, peach, grey, brown, multicolour flashes
• Optical Phenomenon: adularescence (soft, floating glow)
• Clarity: usually translucent; higher clarity increases glow intensity
• Composition: feldspar group (orthoclase + albite layers)
• Hardness: 6 – 6.5 on Mohs scale
• Cut Style: typically cabochon to enhance adularescence
• Origin: Sri Lanka, India, Madagascar, Myanmar
• Special Varieties: blue moonstone, peach moonstone, rainbow moonstone
Value Factors
- • Strength of adularescence: the brighter and more concentrated the glow, the higher the value
• Colour of the sheen: premium stones show a vivid blue glow on a colourless or transparent body
• Transparency: cleaner stones with minimal inclusions command higher prices
• Absence of cracks or layers: structural regularity improves visual quality
• Size: larger stones with strong glow are rare and highly valued
• Origin: top-quality Sri Lankan material is especially prized
• Overall appearance: symmetry, polish, and smoothness of cabochon dome affect desirability
spinels
DESCRIPTION
Spinel is a remarkable gemstone celebrated for its brilliance, durability, and the extraordinary range of vivid colours it can display. Throughout history, many of the world’s most famous “rubies” were later discovered to be red spinels—proof of the gem’s intense natural beauty and its long-standing association with royalty.
The most coveted variety is fine red spinel, historically known as “Balas ruby,” admired for its fiery tone and exceptional luminosity. Equally prized are vibrant pink and hot-pink spinels, cobalt blue spinels with their electric, sapphire-like glow, and the rarer lavender, violet, and orange hues that give the gem a sophisticated and contemporary appeal. Black spinel, sleek and highly reflective, has also become increasingly popular in modern jewellery design.
Spinel’s remarkable colours are created by trace elements within its crystal structure: chromium produces vivid reds and pinks, cobalt gives rise to intense blues, while iron and vanadium generate elegant lavender, violet, and grey shades. Unlike many gemstones, spinel is frequently found in its natural state and rarely requires heat or enhancement, making its colours particularly valued for their authenticity.
The visual quality of spinel—its brightness, clarity, and depth of colour—depends on both the concentration of these trace elements and the stone’s geographic origin. Renowned sources such as Myanmar, Sri Lanka, Tanzania, and Vietnam are known for producing exceptional material, each with its own distinctive colour profile. This natural diversity, combined with excellent durability, makes spinel one of the most versatile and sought-after gemstones in fine and contemporary jewellery.
CARATTERISTIC
- Mineral Family: Spinel (MgAl₂O₄)
- Mohs Hardness: 8 — highly durable
- Lustre: Vitreous, bright, reflective
- Colours:
- Red, hot pink, cobalt blue, lavender, violet, orange, grey, black
- Red, hot pink, cobalt blue, lavender, violet, orange, grey, black
- Cause of Colour:
- Chromium → red & pink
- Cobalt → vivid blue
- Iron/Vanadium → lavender, violet, grey
- Chromium → red & pink
- Transparency: Transparent to opaque
- Treatments:
- Rare — most spinels are untreated (a major advantage)
- Rare — most spinels are untreated (a major advantage)
- Phenomena:
- Occasionally exhibits fluorescence in pink/red stones
- Occasionally exhibits fluorescence in pink/red stones
- Primary Sources:
- Sri Lanka, Myanmar, Tanzania, Vietnam
- Sri Lanka, Myanmar, Tanzania, Vietnam
- Cut:
- Brilliant cuts enhance sparkle
- Cushion and oval cuts common for fine materialCushion and oval cuts common for fine material
- Brilliant cuts enhance sparkle
Market Value & Collectability
- Value Drivers:
- Colour intensity (top-quality = vivid, pure hues)
- Clarity and brilliance
- Rarity of colour (cobalt blue & vivid hot pink are highly prized)
- Origin (Myanmar & Sri Lanka often command premiums)
- Untreated status (most natural spinels score high here)
- Colour intensity (top-quality = vivid, pure hues)
- Most Valuable Types:
- Cobalt Blue Spinel → extremely rare, premium pricing
- Vivid Red Spinel (Balas Ruby) → historically significant, highly collectible
- Hot Pink Spinel → bright, neon saturation is highly coveted
- Lavender/Violet Spinel → increasingly popular in modern designs
- Cobalt Blue Spinel → extremely rare, premium pricing
- Market Position:
Spinel is experiencing a strong rise in value due to its rarity, durability, and the growing awareness that it is a natural gemstone rarely subjected to treatments—unlike many corundums.
- Ideal For:
- High-end jewellery
- Investment pieces
- Collectors seeking rare colours
- Custom jewellery requiring durability and brilliance
- High-end jewellery
Garnets
DESCRIPTION
Garnets form one of the most diverse and fascinating gemstone families, admired for their natural brilliance and remarkable range of colours. While the deep red garnet is the most widely recognised, the family spans an extraordinary spectrum—from vivid greens and golden yellows to fiery oranges, rich purples, intense pinks, and even the exceptionally rare blue or colour-change varieties.
Each type of garnet possesses its own identity:
- Almandine shows deep, velvety reds,
- Pyrope offers brighter, more vibrant red tones,
- Spessartite captivates with its orange and mandarin hues,
- Tsavorite and Demantoid stand out as two of the world’s most prized green gemstones thanks to their exceptional vividness and high brilliance,
- Colour-change garnet can shift hue depending on the light source, making it one of the rarest and most intriguing members of the family.
This extraordinary diversity arises from variations in chemical composition within the crystal structure. Iron and manganese generate shades from red to purple and orange, while chromium and vanadium produce the vivid green varieties. Because of these compositional differences, garnet is not a single mineral, but a group of related species, each defined by a unique blend of elements.
The visual quality of a garnet depends on its colour intensity, clarity, brilliance, and geographic origin. Regions such as Tanzania, Kenya, Madagascar, Sri Lanka, and Russia are known for producing exceptional material, each with distinct colour signatures. Highly durable and typically untreated, garnets remain valued for their authenticity, versatility, and increasing popularity in modern jewellery.
Characteristics
- Gem Family: Garnet group (not a single mineral but a series of related species)
- Colours: Red, orange, yellow, green (tsavorite, demantoid), pink, purple, brown, black, rare blue & colour-change
- Chemical Causes of Colour:
- Iron & manganese → red, purple, orange
- Chromium & vanadium → vivid greens
- Iron & manganese → red, purple, orange
- Clarity: Varies by type; demantoid often contains “horsetail” inclusions (highly valued)
- Hardness: Average 6.5–7.5 on Mohs scale
- Light Performance: High brilliance; demantoid has exceptional dispersion
- Treatments: Generally untreated; one of the most natural gemstone families
- Typical Origins: Tanzania, Kenya, Madagascar, Sri Lanka, Russia, Namibia, Brazil
- Varieties:
- Almandine – deep red
- Pyrope – vivid red
- Spessartite – orange/mandarin
- Tsavorite – bright green
- Demantoid – neon green with strong dispersion
- Rhodolite – raspberry to purplish tones
- Colour-change garnet – rare, shifts hue depending on light
- Almandine – deep red
Value & Market Notes
- Red Garnets: Common varieties (almandine/pyrope) are accessible; exceptional rhodolite commands higher prices.
- Orange Spessartite: Highly valued, especially “mandarin” specimens from Namibia and Nigeria with strong saturation.
- Green Tsavorite: One of the most valuable garnets; fine clarity and strong green rival emeralds.
- Demantoid: The rarest and most expensive garnet, valued for its brilliance and iconic “horsetail” inclusions.
- Colour-Change Garnet: Extremely rare; strong, dramatic colour shift increases value significantly.
- Market Demand: Rising steadily due to natural, untreated status and increasing interest in unique coloured gemstones.
- Investment Quality Factors:
- Purity and vivid saturation
- Rarity of variety (demantoid, tsavorite, colour-change)
- Origin (Russian demantoid, Kenyan tsavorite)
- Size—fine garnets over 5 ct become exponentially more valuable
- Purity and vivid saturation
Alexandrite
DESCRIPTION
Alexandrite is one of the rarest and most captivating gemstones in the world, renowned for its extraordinary colour-change phenomenon. In natural daylight or cool light, it typically appears green or bluish-green; under incandescent or warm artificial light, however, it transforms into red, purplish-red, or violet tones. This striking duality—often described as “green by day, red by night”—gives alexandrite an almost magical allure, making it highly prized by collectors and fine jewellery designers.
The effect is caused by traces of chromium within the crystal structure of chrysoberyl. Chromium changes the way the stone absorbs and reflects light, allowing it to shift dramatically depending on the light spectrum. The stronger and more distinct this transformation, the more valuable the gemstone.
Natural alexandrite is exceptionally rare, with historic origins in Russia’s Ural Mountains and important deposits in Sri Lanka and Brazil, each contributing subtle variations in tone, clarity, and colour-change intensity. Its rarity, durability, and remarkable optical behaviour place alexandrite among the most exclusive gemstones in contemporary jewellery.
Characteristics
- Mineral: Chrysoberyl (variety exhibiting colour change)
- Chemical cause of colour: Chromium (Cr³⁺)
- Optical phenomenon: Colour change (green → red), occasionally with pleochroism
- Colour range in daylight: Green, blue-green, moss green
- Colour range in warm light: Red, purplish-red, raspberry, violet-red
- Transparency: Transparent to slightly included
- Hardness: 8.5 on Mohs scale
- Typical origins: Russia (Ural), Sri Lanka, Brazil, Madagascar
- Rarity: Extremely rare, especially in larger clean stones
- Treatments: Typically none; natural stones prized for authenticity
Value Factors
- Strength of colour change
The most important value factor.
Full, dramatic green→red shift = highest value.
- Colour quality in both lighting conditions
Pure green in daylight and strong red in incandescent light increase desirability.
- Clarity and transparency
Eye-clean stones command premium prices; inclusions reduce value unless they enhance character (e.g., cat’s-eye alexandrite).
- Size and weight
Fine alexandrite above 1 ct is rare; above 2–3 ct becomes exponentially valuable.
- Origin
Russian Ural alexandrite = legendary and highest priced.
Sri Lankan and Brazilian stones are prized but typically show softer hues.
- Treatment status
Untreated natural alexandrite carries significantly higher value.
- Cut quality
Well-executed cuts maximise colour change and brilliance.
Amethyst
DECRIPTION
Amethyst is one of the most iconic and captivating gemstones of the quartz family, celebrated for its stunning range of violet hues—from soft lilac to deep, intense purple. Long valued as a symbol of balance and clarity, it is cherished in both fine jewellery and modern design for its natural beauty, brilliance, and versatility.
Its colour originates from traces of iron within the quartz structure, later transformed by natural radiation over millions of years. This process produces the gem’s signature violet tones, which vary greatly in depth and saturation. The finest amethysts display a rich, even purple with subtle blue or reddish undertones, while lighter varieties offer a soft, radiant glow. Some stones reveal delicate colour zoning—a natural record of the crystal’s growth—adding individuality to each gem.
The quality of an amethyst is determined by its colour intensity, clarity, and brightness. Regions such as Brazil, Uruguay, and Zambia are renowned for producing high-quality material, each with distinctive visual characteristics ranging from velvety dark purples to vivid, transparent hues. Thanks to its accessible beauty, durability, and enchanting natural variations, amethyst remains one of the most beloved and enduring gemstones in contemporary jewellery.
Characteristics
Colour Range:
Light lilac → deep royal purple (often with blue or red undertones)
Crystal System:
Hexagonal (Quartz)
Hardness:
7 on the Mohs scale — resistant and suitable for everyday jewellery
Clarity:
Typically eye-clean; higher grades show excellent transparency
Optical Features:
• Possible colour zoning
• Pleochroism (purple → reddish-purple)
• Strong brilliance in well-cut stones
Origins:
Brazil, Uruguay, Zambia, Madagascar, Sri Lanka
Value Factors
1. Colour Quality (Primary Factor)
Deep, saturated purple with flashes of blue or red is the most valuable.
Lighter or unevenly coloured stones are more common and lower in price.
2. Clarity
Eye-clean stones with high transparency command higher values.
Inclusions or zoning reduce price.
3. Cut
Precision cutting enhances brilliance and evens out colour zoning.
4. Size
Large amethysts are relatively common, so value increases moderately with size—
but exceptional colour in large stones greatly boosts rarity.
5. Origin (Supplementary Factor)
Uruguayan and Zambian stones often fetch higher prices due to deeper colour.
