/* ── TOC ── */
.bp-toc { max-width: 820px; margin: 0 auto; padding: 44px 24px 0; }
.bp-toc__inner {
background: var(--bp-cream);
border: 1px solid var(--bp-navy10);
padding: 32px 36px;
position: relative;
}
.bp-toc__inner::after {
content: '';
position: absolute;
top: 5px; left: 5px; right: -5px; bottom: -5px;
border: 1px solid rgba(0,15,56,.06);
z-index: -1;
}
.bp-toc__head {
font-family: var(--bp-sans);
font-size: 9px;
font-weight: 600;
letter-spacing: .28em;
text-transform: uppercase;
color: var(--bp-orange);
margin: 0 0 18px 0;
display: flex;
align-items: center;
gap: 12px;
}
.bp-toc__head::after { content: ''; flex: 1; height: 1px; background: var(--bp-navy10); }
.bp-toc__list {
list-style: none !important;
margin: 0 !important;
padding: 0 !important;
display: grid;
grid-template-columns: 1fr 1fr;
gap: 5px 24px;
}
@media (max-width: 520px) { .bp-toc__list { grid-template-columns: 1fr; } }
.bp-toc__item { margin: 0 !important; padding: 0 !important; list-style: none !important; }
.bp-toc__item::before { display: none !important; }
.bp-toc__link {
font-family: var(--bp-sans) !important;
font-size: 12px !important;
font-weight: 500 !important;
letter-spacing: .06em !important;
text-transform: uppercase;
color: var(--bp-navy72) !important;
text-decoration: none !important;
display: flex !important;
align-items: center !important;
gap: 10px !important;
padding: 5px 0 !important;
transition: color .18s;
border: none !important;
}
.bp-toc__num {
font-family: var(--bp-serif);
font-size: 14px;
font-style: italic;
color: var(--bp-ruby);
opacity: .7;
min-width: 22px;
flex-shrink: 0;
}
.bp-toc__link:hover { color: var(--bp-ruby) !important; }
.bp-toc__link:hover .bp-toc__num { opacity: 1; }

/* ── BODY ── */
.bp-body { max-width: 820px; margin: 0 auto; padding: 60px 24px 90px; }
.bp-section { margin-bottom: 72px; }
.bp-section__header {
display: flex;
align-items: flex-start;
gap: 18px;
margin-bottom: 28px;
padding-bottom: 18px;
border-bottom: 1px solid var(--bp-navy10);
}
.bp-section__num {
font-family: var(--bp-serif);
font-size: 50px;
font-weight: 400;
font-style: italic;
color: rgba(30,79,176,.16);
line-height: 1;
flex-shrink: 0;
margin-top: -5px;
}
.bp-section__label {
font-family: var(--bp-sans);
font-size: 9px;
font-weight: 600;
letter-spacing: .28em;
text-transform: uppercase;
color: var(--bp-orange);
margin: 0 0 6px 0;
}
.bp-section__title {
font-family: var(--bp-serif) !important;
font-weight: 400 !important;
font-size: clamp(21px, 3vw, 29px) !important;
line-height: 1.22 !important;
color: var(--bp-navy) !important;
margin: 0 !important;
padding: 0 !important;
border: none !important;
}
.bp-section__title em { font-style: italic; color: var(--bp-ruby); }
.bp-p {
font-family: var(--bp-sans);
font-size: 15px;
line-height: 1.85;
color: var(--bp-navy72);
margin: 0 0 16px 0 !important;
padding: 0;
}
.bp-p:last-child { margin-bottom: 0 !important; }
.bp-p strong { font-weight: 600; color: var(--bp-navy); }
.bp-lead {
font-family: var(--bp-serif);
font-size: 19px;
font-style: italic;
line-height: 1.65;
color: var(--bp-navy);
border-left: 3px solid var(--bp-ruby);
padding: 4px 0 4px 20px;
margin: 0 0 22px 0;
}
.bp-divider {
display: flex;
align-items: center;
gap: 14px;
margin: 52px 0;
}
.bp-divider::before,
.bp-divider::after { content: ''; flex: 1; height: 1px; background: var(--bp-navy10); }

/* ── FIGURE ── */
.bp-figure { margin: 32px 0; }
.bp-figure img {
width: 100%;
height: auto;
display: block;
margin: 0 !important;
}
.bp-figure figcaption {
font-family: var(--bp-sans);
font-size: 11px;
letter-spacing: .04em;
color: var(--bp-navy45);
text-align: center;
margin-top: 10px;
font-style: italic;
}

/* ── TIP ── */
.bp-tip {
border: 1px solid rgba(254,129,57,.30);
background: var(--bp-or-bg);
padding: 24px 28px;
margin: 28px 0;
position: relative;
}
.bp-tip::before {
content: '✦';
position: absolute;
top: -10px; left: 22px;
background: #fffcf4;
padding: 0 8px;
color: var(--bp-orange);
font-size: 13px;
}
.bp-tip__label {
font-family: var(--bp-sans);
font-size: 9px;
font-weight: 600;
letter-spacing: .28em;
text-transform: uppercase;
color: var(--bp-orange);
margin: 0 0 9px 0;
}
.bp-tip__text {
font-family: var(--bp-sans);
font-size: 14px;
line-height: 1.8;
color: var(--bp-navy72);
margin: 0;
}
.bp-tip__text strong { font-weight: 600; color: var(--bp-navy); }

/* ── DUEL ── */
.bp-duel {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 2px;
margin: 32px 0;
background: var(--bp-navy10);
}
@media (max-width: 580px) { .bp-duel { grid-template-columns: 1fr; } }
.bp-duel__card {
padding: 32px 28px;
position: relative;
}
.bp-duel__card--a { background: var(--bp-ruby-pale); }
.bp-duel__card--b { background: var(--bp-white); }
.bp-duel__tag {
font-family: var(--bp-sans);
font-size: 9px;
font-weight: 600;
letter-spacing: .22em;
text-transform: uppercase;
padding: 4px 10px;
display: inline-block;
margin-bottom: 14px;
}
.bp-duel__card--a .bp-duel__tag { background: var(--bp-ruby); color: #fff; }
.bp-duel__card--b .bp-duel__tag { background: var(--bp-navy); color: #fff; }
.bp-duel__img-wrap {
width: 100%;
overflow: hidden;
margin-bottom: 20px;
background: #f0ede8;
}
.bp-duel__img {
width: 100%;
height: auto;
display: block;
margin: 0 !important;
padding: 0 !important;
transition: transform .4s ease;
}
.bp-duel__card:hover .bp-duel__img { transform: scale(1.04); }
.bp-duel__name {
font-family: var(--bp-serif) !important;
font-size: 24px !important;
font-weight: 400 !important;
color: var(--bp-navy) !important;
margin: 0 0 10px 0 !important;
padding: 0 !important;
border: none !important;
}
.bp-duel__desc {
font-family: var(--bp-sans);
font-size: 13px;
line-height: 1.75;
color: var(--bp-navy72);
margin: 0 0 16px 0;
}
.bp-duel__link {
font-family: var(--bp-sans) !important;
font-size: 10px !important;
font-weight: 600 !important;
letter-spacing: .18em !important;
text-transform: uppercase !important;
color: var(--bp-orange) !important;
text-decoration: none !important;
border-bottom: 1px solid rgba(254,129,57,.3) !important;
padding-bottom: 2px !important;
transition: border-color .18s !important;
}
.bp-duel__link:hover { border-color: var(--bp-orange) !important; }

/* ── TABLE ── */
.bp-table-wrap { margin: 32px 0; overflow-x: auto; }
.bp-table {
width: 100%;
border-collapse: collapse !important;
font-size: 14px;
font-family: var(--bp-sans);
}
.bp-table thead tr { border-bottom: 2px solid var(--bp-ruby); }
.bp-table th {
font-family: var(--bp-sans) !important;
font-size: 9px !important;
font-weight: 600 !important;
letter-spacing: .25em !important;
text-transform: uppercase;
color: var(--bp-ruby) !important;
padding: 10px 14px !important;
text-align: left !important;
background: transparent !important;
border: none !important;
}
.bp-table td {
padding: 14px !important;
border: none !important;
border-bottom: 1px solid var(--bp-navy10) !important;
color: var(--bp-navy72) !important;
vertical-align: top;
background: transparent !important;
font-family: var(--bp-sans) !important;
font-size: 14px !important;
}
.bp-table td:first-child {
font-family: var(--bp-serif) !important;
font-size: 16px !important;
font-style: italic;
color: var(--bp-navy) !important;
white-space: nowrap;
}
.bp-table td strong { font-weight: 600; color: var(--bp-navy); }
.bp-table tbody tr:hover td { background: rgba(30,79,176,.04) !important; }
.bp-badge {
display: inline-block;
font-family: var(--bp-sans);
font-size: 10px;
font-weight: 600;
letter-spacing: .1em;
padding: 3px 8px;
}
.bp-badge--ruby { background: var(--bp-ruby-pale); color: var(--bp-ruby); }
.bp-badge--navy { background: rgba(0,15,56,.07); color: var(--bp-navy); }

/* ── CRITERIA ── */
.bp-criteria {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
gap: 14px;
margin: 32px 0;
}
.bp-criterion {
border: 1px solid var(--bp-navy10);
padding: 22px 18px;
background: var(--bp-white);
transition: border-color .18s;
}
.bp-criterion:hover { border-color: var(--bp-ruby); }
.bp-criterion__num {
font-family: var(--bp-serif);
font-size: 36px;
font-style: italic;
color: rgba(30,79,176,.18);
line-height: 1;
margin-bottom: 7px;
}
.bp-criterion__title {
font-family: var(--bp-sans);
font-size: 11px;
font-weight: 600;
letter-spacing: .14em;
text-transform: uppercase;
color: var(--bp-navy);
margin: 0 0 8px 0;
}
.bp-criterion__text {
font-family: var(--bp-sans);
font-size: 12px;
line-height: 1.72;
color: var(--bp-navy45);
margin: 0;
}
.bp-criterion__title a {
color: var(--bp-navy) !important;
text-decoration: none !important;
border-bottom: 1px solid rgba(30,79,176,.35) !important;
}
.bp-criterion__title a:hover { color: var(--bp-ruby) !important; }

/* ── ORIGINS ── */
.bp-colors {
display: grid;
grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
gap: 1px;
margin: 32px 0;
background: var(--bp-navy10);
border: 1px solid var(--bp-navy10);
}
.bp-color {
background: var(--bp-cream);
padding: 26px 24px;
position: relative;
transition: background .2s;
}
.bp-color:hover { background: #fdf9f5; }
.bp-color::before {
content: '';
position: absolute;
top: 0; left: 0;
width: 3px; height: 100%;
opacity: .85;
}
.bp-color--mogok::before { background: #1a3f9e; }
.bp-color--mozam::before { background: #2f5fc9; }
.bp-color--ceylan::before { background: #5b82e0; }
.bp-color--autres::before { background: #12306e; }
.bp-color__name {
font-family: var(--bp-serif);
font-size: 19px;
color: var(--bp-navy);
margin: 0 0 3px 0;
}
.bp-color__sub {
font-family: var(--bp-sans);
font-size: 9px;
font-weight: 600;
letter-spacing: .2em;
text-transform: uppercase;
color: var(--bp-orange);
margin: 0 0 10px 0;
display: block;
}
.bp-color__desc {
font-family: var(--bp-sans);
font-size: 13px;
line-height: 1.7;
color: var(--bp-navy72);
margin: 0;
}

/* ── BUDGET ── */
.bp-budgets {
display: grid;
grid-template-columns: repeat(3, 1fr);
gap: 14px;
margin: 32px 0;
}
@media (max-width: 620px) { .bp-budgets { grid-template-columns: 1fr; } }
.bp-budget {
border: 1px solid var(--bp-navy10);
padding: 28px 22px;
background: var(--bp-white);
transition: border-color .18s, transform .18s;
}
.bp-budget:hover { border-color: var(--bp-ruby); transform: translateY(-2px); }
.bp-budget--featured {
background: var(--bp-navy);
border-color: var(--bp-navy);
}
.bp-budget__amount {
font-family: var(--bp-serif);
font-size: 26px;
font-weight: 400;
font-style: italic;
color: var(--bp-ruby);
margin-bottom: 4px;
display: block;
}
.bp-budget--featured .bp-budget__amount { color: var(--bp-orange); }
.bp-budget__label {
font-family: var(--bp-sans);
font-size: 9px;
font-weight: 600;
letter-spacing: .22em;
text-transform: uppercase;
color: var(--bp-navy45);
margin-bottom: 18px;
display: block;
}
.bp-budget--featured .bp-budget__label { color: rgba(255,255,255,.45); }
.bp-budget__row {
font-family: var(--bp-sans);
font-size: 13px;
line-height: 1.75;
color: var(--bp-navy72);
padding: 10px 0;
border-top: 1px solid var(--bp-navy10);
}
.bp-budget--featured .bp-budget__row { color: rgba(255,255,255,.7); border-color: rgba(255,255,255,.1); }
.bp-budget__row strong { font-weight: 600; color: var(--bp-navy); }
.bp-budget--featured .bp-budget__row strong { color: #fff; }

/* ── COMPARISON (stones) ── */
.bp-profiles {
display: grid;
grid-template-columns: 1fr 1fr;
gap: 14px;
margin: 32px 0;
}
@media (max-width: 580px) { .bp-profiles { grid-template-columns: 1fr; } }
.bp-profile {
border: 1px solid var(--bp-navy10);
padding: 28px 24px;
background: var(--bp-white);
}
.bp-profile__tag {
font-family: var(--bp-sans);
font-size: 9px;
font-weight: 600;
letter-spacing: .22em;
text-transform: uppercase;
padding: 4px 10px;
display: inline-block;
margin-bottom: 14px;
background: var(--bp-ruby-pale); color: var(--bp-ruby);
}
.bp-profile__img-wrap {
width: 100%;
overflow: hidden;
margin-bottom: 20px;
background: #f0ede8;
}
.bp-profile__img {
width: 100%;
height: auto;
display: block;
margin: 0 !important;
padding: 0 !important;
transition: transform .4s ease;
}
.bp-profile:hover .bp-profile__img { transform: scale(1.04); }
.bp-profile__title {
font-family: var(--bp-serif) !important;
font-size: 20px !important;
font-weight: 400 !important;
font-style: italic;
color: var(--bp-navy) !important;
margin: 0 0 10px 0 !important;
padding: 0 !important;
border: none !important;
}
.bp-profile__desc {
font-family: var(--bp-sans);
font-size: 13px;
line-height: 1.75;
color: var(--bp-navy72);
margin: 0 0 14px 0;
}
.bp-profile__link {
font-family: var(--bp-sans) !important;
font-size: 10px !important;
font-weight: 600 !important;
letter-spacing: .16em !important;
text-transform: uppercase !important;
color: var(--bp-orange) !important;
text-decoration: none !important;
border-bottom: 1px solid rgba(254,129,57,.3) !important;
padding-bottom: 2px !important;
transition: border-color .18s !important;
}
.bp-profile__link:hover { border-color: var(--bp-orange) !important; }

/* ── FAQ ── */
.bp-faq { margin: 32px 0; }
.bp-faq__item {
border-bottom: 1px solid var(--bp-navy10);
padding: 22px 0;
}
.bp-faq__item:first-child { border-top: 1px solid var(--bp-navy10); }
.bp-faq__q {
font-family: var(--bp-serif);
font-size: 18px;
font-style: italic;
color: var(--bp-navy);
margin: 0 0 10px 0;
display: flex;
align-items: flex-start;
gap: 14px;
}
.bp-faq__q::before {
content: 'Q';
font-family: var(--bp-sans);
font-style: normal;
font-size: 9px;
font-weight: 700;
letter-spacing: .1em;
color: var(--bp-ruby);
background: var(--bp-ruby-pale);
padding: 3px 7px;
flex-shrink: 0;
margin-top: 4px;
}
.bp-faq__a {
font-family: var(--bp-sans);
font-size: 14px;
line-height: 1.8;
color: var(--bp-navy72);
margin: 0;
padding-left: 36px;
}

/* ── SEO LINK ── */
.bp-seo-link {
color: inherit !important;
text-decoration: underline !important;
text-decoration-color: rgba(0,15,56,.25) !important;
text-underline-offset: 2px !important;
transition: text-decoration-color .18s, color .18s !important;
}
.bp-seo-link:hover {
color: var(--bp-ruby) !important;
text-decoration-color: var(--bp-ruby) !important;
}

/* ── CTA ── */
.bp-cta {
background: var(--bp-cream);
padding: 56px 40px;
text-align: center;
position: relative;
overflow: hidden;
border-top: 1px solid var(--bp-navy10);
}
.bp-cta::before {
content: '';
position: absolute; inset: 0;
background: radial-gradient(ellipse 70% 40% at 50% 100%, rgba(30,79,176,.06) 0%, transparent 70%);
pointer-events: none;
}
.bp-cta__orn {
display: flex;
align-items: center;
justify-content: center;
gap: 12px;
margin-bottom: 26px;
opacity: .35;
}
.bp-cta__orn::before,
.bp-cta__orn::after { content: ''; display: block; width: 50px; height: 1px; background: var(--bp-navy); }
.bp-cta__title {
font-family: var(--bp-serif) !important;
font-weight: 400 !important;
font-size: clamp(22px, 4vw, 36px) !important;
color: var(--bp-navy) !important;
margin: 0 0 14px 0 !important;
line-height: 1.22 !important;
padding: 0 !important;
border: none !important;
}
.bp-cta__title em { font-style: italic; color: var(--bp-ruby); }
.bp-cta__sub {
font-family: var(--bp-sans);
font-size: 14px;
color: var(--bp-navy72);
max-width: 460px;
margin: 0 auto 32px auto;
line-height: 1.78;
}
.bp-cta__btns {
display: flex;
gap: 12px;
justify-content: center;
flex-wrap: wrap;
}
.bp-btn--primary {
display: inline-block !important;
padding: 13px 32px !important;
background: var(--bp-ruby) !important;
color: var(--bp-white) !important;
font-family: var(--bp-sans) !important;
font-size: 11px !important;
font-weight: 600 !important;
letter-spacing: .2em !important;
text-transform: uppercase !important;
text-decoration: none !important;
border: none !important;
border-radius: 0 !important;
transition: background .18s;
}
.bp-btn--primary:hover { background: var(--bp-ruby-deep) !important; color: var(--bp-white) !important; }
.bp-btn--secondary {
display: inline-block !important;
padding: 12px 32px !important;
border: 1px solid rgba(0,15,56,.25) !important;
color: var(--bp-navy) !important;
font-family: var(--bp-sans) !important;
font-size: 11px !important;
font-weight: 500 !important;
letter-spacing: .2em !important;
text-transform: uppercase !important;
text-decoration: none !important;
background: transparent !important;
border-radius: 0 !important;
transition: border-color .18s, color .18s;
}
.bp-btn--secondary:hover { border-color: var(--bp-ruby) !important; color: var(--bp-ruby) !important; }

/* ── REVEAL ── */
.bp-reveal {
opacity: 0;
transform: translateY(16px);
transition: opacity .55s ease, transform .55s ease;
}
.bp-reveal--visible { opacity: 1; transform: none; }

@keyframes bp-fadeup {
from { opacity: 0; transform: translateY(18px); }
to { opacity: 1; transform: none; }
}
.bp-hero__title { animation: bp-fadeup .75s ease both; }
.bp-hero__sub { animation: bp-fadeup .75s ease .12s both; }
.bp-hero__meta { animation: bp-fadeup .75s ease .24s both; }

@media (max-width: 600px) {
.bp-cta { padding: 40px 22px; }
.bp-section__num { font-size: 36px; }
.bp-budgets { grid-template-columns: 1fr; }
}

Bonnot Paris · The Journal of Precious Stones 2026

Blue Sapphire: the complete guide — meaning, price and origin

Colour, origins, symbolism, quality and price — everything you need to know before choosing a blue sapphire, from our coloured stone dealers.

By François Deprez, founder · Complete guide · 9 min · Updated July 2026

Of all coloured stones, the blue sapphire is the most universally beloved. Stone of kings, sages and solemn vows, it has crossed the centuries as the very symbol of fidelity — and remains, to this day, the most chosen coloured alternative for an engagement ring.

As a specialist colour-stone dealer and the only French member of the ICA (International Coloured Gemstone Association), we select our sapphires directly at source, through our offices in Sri Lanka and Bangkok. This is our complete guide to understanding, evaluating and choosing a blue sapphire with confidence.

01

At a glance

The queen of engagement stones

Blue sapphire belongs to the same mineral family as ruby, and reaches a hardness of 9 out of 10 on the Mohs scale. Its colour arises from a combination of iron and titanium. Two shades dominate the top of the market: royal blue, deep and saturated, and cornflower blue, lighter and velvety. From rough gem to finished jewel, here are the two faces of the blue sapphire.

The stone

The royal blue sapphire

An intense, deep and saturated blue: the most sought-after shade among great sapphires. Here, a 3.60 ct stone from Sri Lanka, ready to become the heart of a bespoke creation. The definitive reference for blue.

Discover our blue sapphires →

The creation

The daisy ring

The same blue, elevated: a royal blue sapphire of 1.72 ct encircled by a rosette of marquise-cut diamonds, set in yellow gold. A bespoke creation conceived around this exceptional stone.

View blue sapphire rings →

Our position

Royal blue or cornflower, Ceylon or Madagascar: there is no single “best” blue in absolute terms. The finest sapphire is the one whose shade speaks to you, seen in natural light. This guide gives you the tools to compare what is truly comparable — and to pay a fair price for every stone.

02

Fundamentals & meaning

Understanding blue sapphire in three minutes

The word "sapphire" comes from the Latin sapphirus, itself derived from the Greek sappheiros, which referred to a blue stone. Without any colour qualifier, "sapphire" still always means blue. It belongs to the same mineral species as the ruby — only colour sets them apart, and here it is the iron-titanium combination that produces the blue.

With a hardness of 9/10, it is one of the most resistant stones in existence, second only to the diamond. In practice: it will not scratch against everyday objects, it withstands knocks and has no fear of water — a decisive advantage for an engagement ring worn every day, far more so than an emerald, which is considerably more fragile.

The meaning of the blue sapphire

Since Antiquity, the blue sapphire has symbolised fidelity, wisdom, sincerity and protection. Long worn by kings and clergy alike, it embodies lasting commitment — hence its place on some of the most celebrated engagement rings in history. It is also the birthstone for September and the gemstone of the 45th wedding anniversary.

03

The geography of the blue sapphire

The origins that make the difference

For blue sapphires more than for any other colour, origin leaves a recognisable signature — and carries considerable weight in value. Four major sources define the market.

Kashmir

The legend

The most sought-after sapphires in the world: a velvety cornflower blue with a slight violet cast and an inimitable brilliance. Production today is virtually non-existent, making these stones of extreme rarity and collector standing.

Sri Lanka — Ceylon

The living reference

The principal source of high-quality sapphires for centuries. From pale blue to royal blue, with that characteristic velvety brilliance and a subtle hint of mauve that defines the "Ceylon blue".

Madagascar

2nd largest source worldwide

Now the second largest source in the world, the island yields blues that are often more saturated, of a quality comparable to modern Ceylon — and at an excellent price-to-quality ratio, subject to export restrictions.

Burma, Australia & others

The complementary sources

Burma (Mogok) yields intense, luminous royal blues. Australia and Thailand produce darker blues with a high iron content. Montana (United States) completes the global picture.

Royal blue or cornflower blue?

Two terms recur constantly. Royal blue describes a deep, intense and highly saturated blue — the benchmark of the great sapphires. Cornflower blue, emblematic of Kashmir, is a lighter, velvety blue with a delicate, slightly violet nuance. Both designations are assigned by gemological laboratories and command a significant premium; between the two, it is entirely a matter of taste.

04

Assessing a stone

The 4 criteria that determine the price

As with the diamond, the value of a blue sapphire is read through a handful of key criteria. Unlike the diamond, however, colour takes precedence over everything else — with origin coming a close second.

01

Colour (the defining criterion)

Hue, tone and saturation. The ideal: a vivid, deep blue — neither too dark nor greyish. A grey-tinged or overly dark blue can lose half its value. This is what weighs most heavily in the price.

02

Clarity

Sapphires frequently display fine natural inclusions (known as "silk"), which are discreet and serve to authenticate the stone. A sapphire that appears perfectly clean and is priced very low should arouse suspicion.

03

Cut

A well-proportioned cut revives the blue and the brilliance, and distributes colour evenly. The cutter must always balance weight retention against revealing the finest possible hue.

04

Weight (carat)

Price rises exponentially with weight: a 3 ct sapphire is worth far more than three times a 1 ct stone. Beyond 2 carats, rarity drives the per-carat price sharply upward.

The Bonnot Paris approach

Every sapphire we offer is accompanied by an independent laboratory certificate (SSEF, GRS, ICA, Bellerophon…) attesting its origin, treatment and characteristics. Our direct sourcing, with no intermediaries, ensures you receive the stone at its true market value.

05

Treatment

Heated or unheated blue sapphire?

Heating is an age-old treatment, practised since antiquity at very high temperatures (up to 1,800 °C) to intensify colour and improve transparency. Approximately 90 % of sapphires on the market are heated: this is an internationally accepted standard, and there is nothing deceptive about it provided it is declared on the certificate.

An unheated sapphire ("no heat" or "NH") retains all its natural characteristics. Rarer by nature, it commands a premium of around 30 % for stones of 1 to 2 carats — a premium that can be multiplied tenfold or more for larger weights and finer colours.

Our commitment

Bonnot Paris offers both options — heated and unheated — always in complete transparency. We do not, however, offer any sapphire treated with beryllium or lead glass, nor any synthetic stone: these contested processes alter the very nature of the gem and have no place in an exceptional creation.

06

Budget

How much does a blue sapphire cost?

The price of a blue sapphire varies enormously according to origin, colour, clarity and treatment. The following are concrete reference points, expressed as price per carat for a fine-quality stone.

800 – 1,500 €
per carat · entry level

Madagascar or Ceylon heated, good quality, ~1 carat.

The finest entry point into a genuinely certified blue sapphire.

1,500 – 4,000 €
per carat · fine quality

Royal blue or cornflower blue, 1 to 2 carats, vivid colour and careful clarity.

The ideal balance for an exceptional ring.

5,000 – 20,000 €
per carat · gem quality

Ceylon / Madagascar unheated, gem quality, larger carats.

A stone of lasting value — Kashmir stands in a category of its own.

At the very top of the market, Kashmir sapphires command prices of several tens of thousands of euros per carat. As a point of reference, a 27-carat Kashmir blue sapphire sold for nearly 2.1 million euros at auction in 2021 — a figure that speaks to the extraordinary rarity of the finest stones.

The Bonnot Paris model

Through our direct sourcing from our offices in Sri Lanka and Bangkok, you pay the true value of the stone — not the successive margins of three or four intermediaries. For a given budget, you access a quality that is generally superior to what traditional retailers can offer.

07

Avoiding confusion

Blue sapphire or another stone? How to tell them apart

Several blue gemstones can be mistaken for sapphire. Some are beautiful stones in their own right — but none can match its hardness or its rarity. Here is how to find your bearings.

Stone	What sets it apart	Hardness
Blue sapphire	Corindon The most noble blue, exceptional rarity and outstanding hardness.	9 / 10
Tanzanite	Intense blue-violet yet far softer and more fragile, and found nowhere else on earth (Tanzania). Less suited to everyday wear.	6 – 7
Blue spinel	Often natural and unheated, with a greyer or steely blue. A fine alternative, and rarer in fine jewellery.	8 / 10
Aquamarine	A light, fresh and luminous blue, softer in character. Accessible, yet less saturated in colour and less hard than sapphire.	7.5 – 8

The modern shade

The teal sapphire

For those who love sapphire but seek a more singular hue: a blue-green between ocean and lagoon, the rising star of contemporary fine jewellery.

Discover the teal sapphire →

The pink-orange rarity

The padparadscha

The other great fancy sapphire: a delicate, exceptionally rare pink-orange, among the most coveted hues in the world, for those who wish to step beyond blue.

Discover the padparadscha →

08

Inspiration

Blue sapphire in an engagement ring

Timeless by nature, blue sapphire lends itself to every style — from the purest solitaire to the most elaborate surround. Here are four directions drawn from bespoke creations, to help you imagine your own.

01

The daisy

An oval sapphire encircled by a rosette of marquise-cut diamonds, set in yellow gold. Romantic and radiant, a style that lets the centre stone bloom.

02

The solitaire

The stone alone, on platinum, in complete purity. A Sri Lankan blue shown to its fullest, without distraction. Timeless and refined.

03

Rose gold

A warm and contemporary contrast: the deep blue of the sapphire softened by the warmth of rose gold. Elegant and of the moment.

04

The unheated

For the purist: an entirely natural, unheated blue sapphire, set with quiet restraint so the stone may speak for itself.

Bespoke

Each of these rings is a one-of-a-kind piece, built around a directly sourced stone. You may draw inspiration from any of them to imagine your own: we interpret the spirit of a design without ever reproducing it identically. Discover bespoke creation →

09

Frequently asked questions

Everything you may wonder about blue sapphire

What is a blue sapphire?

It is the most iconic variety of sapphire, from the same family as ruby. Its blue colour comes from iron and titanium. With a hardness of 9/10, it ranks among the most durable stones, second only to diamond, and ranges from sky blue to royal blue.

What does the blue sapphire symbolise?

Since Antiquity, it has symbolised fidelity, wisdom and sincerity. Long associated with royalty, it embodies lasting commitment — a powerful sentiment for an engagement ring. It is also the birthstone for September and the gemstone of the 45th wedding anniversary.

Where do the finest blue sapphires come from?

Kashmir (velvety cornflower blue) remains the most coveted benchmark, though its output is now extremely rare. Sri Lanka (Ceylon) is the leading source of high-quality stones, and Madagascar the second largest worldwide. Burma, Australia and Montana round out the major origins. Bonnot Paris sources directly through its offices in Sri Lanka and Bangkok.

Royal blue or cornflower blue?

Royal blue is a deep, intense and saturated blue — the benchmark of great sapphires. Cornflower blue is a lighter, velvety shade with a delicate violet undertone, emblematic of Kashmir. Both are highly sought after and command premium prices; the choice comes down to personal taste.

How much does a blue sapphire cost?

Expect approximately €800 to €1,500 per carat for a good-quality heated blue sapphire (around 1 ct), €1,500 to €4,000 per carat for a fine royal blue or cornflower blue of 1 to 2 carats, and €5,000 to €20,000 per carat (and well beyond) for a gem-quality unheated stone. Kashmir sits in a category of its own.

Heated or unheated: what is the difference?

Heat treatment enhances colour and clarity: approximately 90% of sapphires are heated, an accepted industry standard. An unheated sapphire retains its entirely natural characteristics and commands roughly 30% more (and considerably more in larger sizes). Bonnot Paris offers both and excludes any beryllium or lead-glass treatment.

Ready to choose your blue sapphire?

Meet our experts to discover a curated selection of certified blue sapphires, sourced directly in Sri Lanka and Madagascar — or let us help you imagine an entirely bespoke creation.

Create my blue sapphire ring
View our blue sapphires

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Bonnot Paris · The Journal of Precious Stones 2026

Blue Sapphire: the complete guide — meaning, price and origin

Colour, origins, symbolism, quality and price — everything you need to know before choosing a blue sapphire, from our coloured stone dealers.

By François Deprez, founder · Complete guide · 9 min · Updated July 2026

Of all coloured stones, the blue sapphire is the most universally beloved. Stone of kings, sages and solemn vows, it has crossed the centuries as the very symbol of fidelity — and remains, to this day, the most chosen coloured alternative for an engagement ring.

As a specialist colour-stone dealer and the only French member of the ICA (International Coloured Gemstone Association), we select our sapphires directly at source, through our offices in Sri Lanka and Bangkok. This is our complete guide to understanding, evaluating and choosing a blue sapphire with confidence.

01

At a glance

The queen of engagement stones

Blue sapphire belongs to the same mineral family as ruby, and reaches a hardness of 9 out of 10 on the Mohs scale. Its colour arises from a combination of iron and titanium. Two shades dominate the top of the market: royal blue, deep and saturated, and cornflower blue, lighter and velvety. From rough gem to finished jewel, here are the two faces of the blue sapphire.

The stone

The royal blue sapphire

An intense, deep and saturated blue: the most sought-after shade among great sapphires. Here, a 3.60 ct stone from Sri Lanka, ready to become the heart of a bespoke creation. The definitive reference for blue.

Discover our blue sapphires →

The creation

The daisy ring

The same blue, elevated: a royal blue sapphire of 1.72 ct encircled by a rosette of marquise-cut diamonds, set in yellow gold. A bespoke creation conceived around this exceptional stone.

View blue sapphire rings →

Our position

Royal blue or cornflower, Ceylon or Madagascar: there is no single “best” blue in absolute terms. The finest sapphire is the one whose shade speaks to you, seen in natural light. This guide gives you the tools to compare what is truly comparable — and to pay a fair price for every stone.

02

Fundamentals & meaning

Understanding blue sapphire in three minutes

The word "sapphire" comes from the Latin sapphirus, itself derived from the Greek sappheiros, which referred to a blue stone. Without any colour qualifier, "sapphire" still always means blue. It belongs to the same mineral species as the ruby — only colour sets them apart, and here it is the iron-titanium combination that produces the blue.

With a hardness of 9/10, it is one of the most resistant stones in existence, second only to the diamond. In practice: it will not scratch against everyday objects, it withstands knocks and has no fear of water — a decisive advantage for an engagement ring worn every day, far more so than an emerald, which is considerably more fragile.

The meaning of the blue sapphire

Since Antiquity, the blue sapphire has symbolised fidelity, wisdom, sincerity and protection. Long worn by kings and clergy alike, it embodies lasting commitment — hence its place on some of the most celebrated engagement rings in history. It is also the birthstone for September and the gemstone of the 45th wedding anniversary.

03

The geography of the blue sapphire

The origins that make the difference

For blue sapphires more than for any other colour, origin leaves a recognisable signature — and carries considerable weight in value. Four major sources define the market.

Kashmir

The legend

The most sought-after sapphires in the world: a velvety cornflower blue with a slight violet cast and an inimitable brilliance. Production today is virtually non-existent, making these stones of extreme rarity and collector standing.

Sri Lanka — Ceylon

The living reference

The principal source of high-quality sapphires for centuries. From pale blue to royal blue, with that characteristic velvety brilliance and a subtle hint of mauve that defines the "Ceylon blue".

Madagascar

2nd largest source worldwide

Now the second largest source in the world, the island yields blues that are often more saturated, of a quality comparable to modern Ceylon — and at an excellent price-to-quality ratio, subject to export restrictions.

Burma, Australia & others

The complementary sources

Burma (Mogok) yields intense, luminous royal blues. Australia and Thailand produce darker blues with a high iron content. Montana (United States) completes the global picture.

Royal blue or cornflower blue?

Two terms recur constantly. Royal blue describes a deep, intense and highly saturated blue — the benchmark of the great sapphires. Cornflower blue, emblematic of Kashmir, is a lighter, velvety blue with a delicate, slightly violet nuance. Both designations are assigned by gemological laboratories and command a significant premium; between the two, it is entirely a matter of taste.

04

Assessing a stone

The 4 criteria that determine the price

As with the diamond, the value of a blue sapphire is read through a handful of key criteria. Unlike the diamond, however, colour takes precedence over everything else — with origin coming a close second.

01

Colour (the defining criterion)

Hue, tone and saturation. The ideal: a vivid, deep blue — neither too dark nor greyish. A grey-tinged or overly dark blue can lose half its value. This is what weighs most heavily in the price.

02

Clarity

Sapphires frequently display fine natural inclusions (known as "silk"), which are discreet and serve to authenticate the stone. A sapphire that appears perfectly clean and is priced very low should arouse suspicion.

03

Cut

A well-proportioned cut revives the blue and the brilliance, and distributes colour evenly. The cutter must always balance weight retention against revealing the finest possible hue.

04

Weight (carat)

Price rises exponentially with weight: a 3 ct sapphire is worth far more than three times a 1 ct stone. Beyond 2 carats, rarity drives the per-carat price sharply upward.

The Bonnot Paris approach

Every sapphire we offer is accompanied by an independent laboratory certificate (SSEF, GRS, ICA, Bellerophon…) attesting its origin, treatment and characteristics. Our direct sourcing, with no intermediaries, ensures you receive the stone at its true market value.

05

Treatment

Heated or unheated blue sapphire?

Heating is an age-old treatment, practised since antiquity at very high temperatures (up to 1,800 °C) to intensify colour and improve transparency. Approximately 90 % of sapphires on the market are heated: this is an internationally accepted standard, and there is nothing deceptive about it provided it is declared on the certificate.

An unheated sapphire ("no heat" or "NH") retains all its natural characteristics. Rarer by nature, it commands a premium of around 30 % for stones of 1 to 2 carats — a premium that can be multiplied tenfold or more for larger weights and finer colours.

Our commitment

Bonnot Paris offers both options — heated and unheated — always in complete transparency. We do not, however, offer any sapphire treated with beryllium or lead glass, nor any synthetic stone: these contested processes alter the very nature of the gem and have no place in an exceptional creation.

06

Budget

How much does a blue sapphire cost?

The price of a blue sapphire varies enormously according to origin, colour, clarity and treatment. The following are concrete reference points, expressed as price per carat for a fine-quality stone.

800 – 1,500 €
per carat · entry level

Madagascar or Ceylon heated, good quality, ~1 carat.

The finest entry point into a genuinely certified blue sapphire.

1,500 – 4,000 €
per carat · fine quality

Royal blue or cornflower blue, 1 to 2 carats, vivid colour and careful clarity.

The ideal balance for an exceptional ring.

5,000 – 20,000 €
per carat · gem quality

Ceylon / Madagascar unheated, gem quality, larger carats.

A stone of lasting value — Kashmir stands in a category of its own.

At the very top of the market, Kashmir sapphires command prices of several tens of thousands of euros per carat. As a point of reference, a 27-carat Kashmir blue sapphire sold for nearly 2.1 million euros at auction in 2021 — a figure that speaks to the extraordinary rarity of the finest stones.

The Bonnot Paris model

Through our direct sourcing from our offices in Sri Lanka and Bangkok, you pay the true value of the stone — not the successive margins of three or four intermediaries. For a given budget, you access a quality that is generally superior to what traditional retailers can offer.

07

Avoiding confusion

Blue sapphire or another stone? How to tell them apart

Several blue gemstones can be mistaken for sapphire. Some are beautiful stones in their own right — but none can match its hardness or its rarity. Here is how to find your bearings.

Stone	What sets it apart	Hardness
Blue sapphire	Corindon The most noble blue, exceptional rarity and outstanding hardness.	9 / 10
Tanzanite	Intense blue-violet yet far softer and more fragile, and found nowhere else on earth (Tanzania). Less suited to everyday wear.	6 – 7
Blue spinel	Often natural and unheated, with a greyer or steely blue. A fine alternative, and rarer in fine jewellery.	8 / 10
Aquamarine	A light, fresh and luminous blue, softer in character. Accessible, yet less saturated in colour and less hard than sapphire.	7.5 – 8

The modern shade

The teal sapphire

For those who love sapphire but seek a more singular hue: a blue-green between ocean and lagoon, the rising star of contemporary fine jewellery.

Discover the teal sapphire →

The pink-orange rarity

The padparadscha

The other great fancy sapphire: a delicate, exceptionally rare pink-orange, among the most coveted hues in the world, for those who wish to step beyond blue.

Discover the padparadscha →

08

Inspiration

Blue sapphire in an engagement ring

Timeless by nature, blue sapphire lends itself to every style — from the purest solitaire to the most elaborate surround. Here are four directions drawn from bespoke creations, to help you imagine your own.

01

The daisy

An oval sapphire encircled by a rosette of marquise-cut diamonds, set in yellow gold. Romantic and radiant, a style that lets the centre stone bloom.

02

The solitaire

The stone alone, on platinum, in complete purity. A Sri Lankan blue shown to its fullest, without distraction. Timeless and refined.

03

Rose gold

A warm and contemporary contrast: the deep blue of the sapphire softened by the warmth of rose gold. Elegant and of the moment.

04

The unheated

For the purist: an entirely natural, unheated blue sapphire, set with quiet restraint so the stone may speak for itself.

Bespoke

Each of these rings is a one-of-a-kind piece, built around a directly sourced stone. You may draw inspiration from any of them to imagine your own: we interpret the spirit of a design without ever reproducing it identically. Discover bespoke creation →

09

Frequently asked questions

Everything you may wonder about blue sapphire

What is a blue sapphire?

It is the most iconic variety of sapphire, from the same family as ruby. Its blue colour comes from iron and titanium. With a hardness of 9/10, it ranks among the most durable stones, second only to diamond, and ranges from sky blue to royal blue.

What does the blue sapphire symbolise?

Since Antiquity, it has symbolised fidelity, wisdom and sincerity. Long associated with royalty, it embodies lasting commitment — a powerful sentiment for an engagement ring. It is also the birthstone for September and the gemstone of the 45th wedding anniversary.

Where do the finest blue sapphires come from?

Kashmir (velvety cornflower blue) remains the most coveted benchmark, though its output is now extremely rare. Sri Lanka (Ceylon) is the leading source of high-quality stones, and Madagascar the second largest worldwide. Burma, Australia and Montana round out the major origins. Bonnot Paris sources directly through its offices in Sri Lanka and Bangkok.

Royal blue or cornflower blue?

Royal blue is a deep, intense and saturated blue — the benchmark of great sapphires. Cornflower blue is a lighter, velvety shade with a delicate violet undertone, emblematic of Kashmir. Both are highly sought after and command premium prices; the choice comes down to personal taste.

How much does a blue sapphire cost?

Expect approximately €800 to €1,500 per carat for a good-quality heated blue sapphire (around 1 ct), €1,500 to €4,000 per carat for a fine royal blue or cornflower blue of 1 to 2 carats, and €5,000 to €20,000 per carat (and well beyond) for a gem-quality unheated stone. Kashmir sits in a category of its own.

Heated or unheated: what is the difference?

Heat treatment enhances colour and clarity: approximately 90% of sapphires are heated, an accepted industry standard. An unheated sapphire retains its entirely natural characteristics and commands roughly 30% more (and considerably more in larger sizes). Bonnot Paris offers both and excludes any beryllium or lead-glass treatment.

Ready to choose your blue sapphire?

Meet our experts to discover a curated selection of certified blue sapphires, sourced directly in Sri Lanka and Madagascar — or let us help you imagine an entirely bespoke creation.

Create my blue sapphire ring
View our blue sapphires