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MannoGem high jewelry ring with natural sapphire
Est. 1987 • Independent Gem House • mannogem.net

Rare gems.
Honest light.
Forever jewels.

MannoGem hunts, cuts and sets the world's finest natural rubies, sapphires, emeralds and spinels. No treatments hidden, no stories invented — only certified, traceable beauty for collectors and brides.

Explore collections Our house since 1987 →
38+ yrsGem expertise
12k+Certified stones
100%Natural & disclosed
Engagement ring with diamond on hand
One-of-one • 3.42 ctUNHEATED CEYLON

The Manno Ceylon Sapphire Ring

Cornflower blue, loupe-clean, Gübelin certified. Set in platinum with trapezoid diamonds.

Reserve viewingDetails
◈ Burmese Rubies◈ Ceylon Sapphires◈ Colombian Emeralds◈ Mahenge Spinels◈ Paraiba Tourmalines◈ Alexandrite◈ Burmese Rubies◈ Ceylon Sapphires◈ Colombian Emeralds◈ Mahenge Spinels
01 — About the house

A family obsessed
with true colour.

Founded by gemologist Elio Manno in Bangkok in 1987, MannoGem today unites miners, cutters and goldsmiths under one roof. We buy at source, cut for beauty not weight, and tell you everything.

Gold rings and gemstones at MannoGem atelier Hands holding emerald jewelry

We don't sell stones. We vouch for them.

Every MannoGem gemstone travels with a passport: origin, mine, treatment level, cutting diagram and light performance video. If a ruby is heated, we say so. If an emerald has minor oil, you will know before you pay.

Our atelier in the old merchant quarter cuts 400–600 stones a year and creates only 120 jewels. Slow by design. Each piece is sketched by hand, modelled in 3D, cast in recycled 18k gold or platinum, and polished for 14 hours.

◈ CertifiedSSEF, Gübelin, GIA & Lotus reports on all important stones.
◈ TraceableDirect contracts with 11 mines in Sri Lanka, Mozambique, Colombia.
◈ EthicalNo child labour, fair pay audited, 5% to mining schools.
◈ LifetimeBuy-back, free re-polish, resizing and upgrade program.
Inside our atelierMeet the gemologist →
11Partner mines
4.9★2,300+ reviews
27Master cutters
0Undisclosed treatments
02 — High jewelry

Three universes, one obsession.

From bridal icons to collector suites and men's signets. All made to order in 3–5 weeks, with your stone reserved from day one.

Bridal solitaire diamond ring
Bridal • from $2,900

Luce Promise

Solitaires, toi-et-moi and halo rings built around your centre sapphire, ruby or diamond. Platinum, 18k champagne gold.

DESIGN YOUR RING →
Emerald earrings high jewelry
Collector • 1 of 1

Giardino Segreto

Museum-grade suites: Colombian emeralds, Mahenge spinels, Paraiba tourmalines. One suite a month, never repeated.

VIEW GALLERY →
Gold signet and gemstone jewels
Heritage • from $1,800

Sangue Reale

Signets, cufflinks and pendants with Burmese rubies, alexandrite and black opal. Engraved crest, sealed wax box.

CHOOSE YOUR STONE →
03 — The vault

Stones that hold light forever.

Live inventory changes weekly. All prices include certification, insured delivery and 30-day returns. Tap to reserve for viewing.

Burmese ruby gemstone

Burmese Ruby

Pigeon's blood, Mogok valley. Unheated 1.2–3.8 ct. SSEF certified.

from $8,400 / ctReserve →
Ceylon blue sapphire

Ceylon Sapphire

Cornflower & royal blue. Unheated, loupe-clean. Gübelin papers.

from $3,900 / ctReserve →
Colombian emerald

Colombian Emerald

Muzo minor oil, vivid saturation. 1.5–5 ct pairs & singles.

from $4,200 / ctReserve →
Mahenge pink spinel

Mahenge Spinel

Neon pink, untreated, brilliant cut. Collector favourite 2025.

from $1,850 / ctReserve →
04 — Atelier & craft

From rough to reverence in 214 steps.

Watch your stone being cut via macro video. Approve the sketch, the wax, the setting — then wear it for generations.

Jeweler setting gemstone
Live bench cam
Every commission filmed in 4K macro
Start →
1

Sourcing & selection

We review 2,000 rough stones to keep 20. Origin trip reports and mine videos shared with you.

2

Precision cutting

Cut for light return, not weight retention. 0.01 mm tolerance, hearts & arrows symmetry check.

3

Certification

Independent lab: SSEF, Gübelin or GIA. Treatment, origin and dimensions fully disclosed.

4

Design & setting

Hand sketch → 3D → wax → casting in recycled gold. Pavé under microscope, 14h polish.

5

Lifetime care

Free annual check, re-rhodium, re-polish, insurance valuation and buy-back in writing.

06 — Journal

Learn before you invest.

Buying guides, market notes, treatment alerts and mine stories from our gemologists. New article every week.

Journal launching soon

Our gemologists are preparing buying guides. Contact us for personal advice.

Ask a gemologist →
07 — FAQ

Questions,
answered honestly.

Still unsure? Write to us — a real gemologist replies within 24h, not a bot.

Ask a question

Are your stones 100% natural? +

Yes. We sell only natural earth-mined stones. Any treatment — heat, oil, irradiation — is disclosed in writing and on the certificate. We never sell glass-filled or synthetic as natural.

What certificates do you provide? +

SSEF, Gübelin, GIA or Lotus depending on species and value. Stones above $1,500 always come with an international lab report plus our in-house passport.

Can I return or upgrade? +

30-day free returns, lifetime buy-back at 80% and full upgrade credit if you move to a larger stone within 3 years.

Do you ship internationally insured? +

Yes — fully insured, discreet, duties handled. Hand delivery available in 14 cities for high-value pieces.

How long does a bespoke jewel take? +

3–5 weeks from stone reservation: sketch in 48h, 3D in 7 days, casting and setting in 2–3 weeks, filmed throughout.

Private viewings • Daily 10–19

See the fire in person.

Via dei Gioiellieri 12, Old Merchant Quarter
Also in Geneva & Bangkok by appointment.

Call: +39 02 8736 4410
Mail: [email protected]

Every inquiry gets a loupe, daylight lamps and zero pressure.

◈ GIA trained◈ SSEF partner◈ Since 1987

No spam. No pressure. Reply within 24 hours.