Moissanite Repair Guide: Sizing, Retipping, Heat

Can moissanite be repaired, sized, and retipped safely?

Yes. Moissanite is 9.25 on the Mohs scale and tolerates a jeweler''s torch during normal sizing and soldering — but there is one hard rule: color-treated moissanite must not be retipped with the stone in place using a torch, because torch heat strips the color treatment. That work requires a laser welder. Most moissanite damage at the bench is not the stone''s fault; it is a bench that treated it like a diamond, or like cubic zirconia, instead of like moissanite.

What moissanite actually tolerates

Property	Moissanite	What it means at the bench
Hardness	9.25 Mohs	Harder than sapphire and ruby; second only to diamond. Setting and polishing are safe.
Melting point	~2730°C	Survives normal torch work during sizing and soldering.
Heat behaviour	Minor, temporary colour shift under extreme torch heat	Returns to normal colour after cooling, with correct technique.
Overheating risk	Fracturing or burnt spots	Uncontrolled or prolonged heat is the real hazard, not heat itself.
Colour-treated stones	Treatment is heat-sensitive	Cannot be torch-retipped in place — laser only.

The practical summary: moissanite is more forgiving than most jewelers expect on hardness and general heat, and less forgiving than they expect on treated colour and on sloppy, prolonged heating.

The four repairs people ask about

1. Resizing a moissanite ring

Standard. The stone stays set for most sizing work, and moissanite''s heat tolerance covers normal soldering. Platinum settings still need laser welding for the metal''s sake, not the stone''s.

2. Retipping prongs

This is where technique matters most. On untreated moissanite, careful torch retipping with the stone in place is feasible. On colour-treated moissanite it is not — the treatment is removed by torch heat, and the stone comes out a different colour than it went in. A laser welder puts heat only where it is needed and leaves the treatment intact.

3. Tightening a loose moissanite

Same as any hard stone: the setting is the problem, not the gem. Moissanite''s hardness means it usually survives whatever loosened it, but a stone that has been rattling should be inspected for chipped girdle edges before it is re-seated.

4. Replacing a lost or chipped moissanite

Match matters more than with diamond. Moissanite is produced in defined colour and cut grades; a replacement sourced without matching to the original will read as obviously different next to its neighbours. Bring or ship the whole piece, not just the setting.

How to choose someone to repair moissanite

Ask whether they have a laser welder. If the answer is no, they cannot safely retip colour-treated moissanite in place. That single question filters most of the market.
Ask whether they distinguish moissanite from CZ and lab diamond in intake. Shops that log stone type at intake are shops that route work to the right bench.
Ask what their insurance covers while your piece is with them. For a piece with sentimental value, coverage matters more than price.
Ask for a written quote before work begins. Any repairer that starts without one is not documenting your piece.

Charles & Colvard pieces specifically

RJS is an authorized Charles & Colvard repair partner. That word applies to Charles & Colvard and to no other brand we work on. For other manufacturers'' pieces we say plainly what is true: we repair them, expertly and insured — we are not their authorized service centre.

If your moissanite is still inside its original manufacturer warranty, check the warranty terms first: manufacturers commonly treat third-party alteration as outside the warranty, and that is a decision worth making deliberately rather than discovering afterwards.

Where RJS fits

RJS has been on the bench since 2002, processes 50,000+ pieces a year, and uses laser welding where heat near a stone or a treatment is a risk. Every piece is insured under a Lloyd''s of London Jewelers Block Policy with 100% chain-of-custody tracking, and every repair is quoted in writing after a free evaluation.

Frequently asked questions

Where can I send my Charles & Colvard moissanite for repair? Charles & Colvard handles warranty registration and warranty service directly. For paid repair, sizing, retipping, and restoration, RJS is an authorized Charles & Colvard repair partner and accepts insured mail-in work nationwide. If your piece is under warranty, review the warranty terms before choosing a third party.

Can you resize a moissanite ring? Yes. Moissanite tolerates the heat of normal sizing and soldering work, and in most cases the stone stays set. Platinum settings require laser welding because of the metal, not the stone.

Does moissanite get damaged by a jeweler''s torch? Not under correct technique. Moissanite withstands torch temperatures used in repair and shows only a minor, temporary colour shift that reverses on cooling. Overheating — uncontrolled or prolonged heat — can cause fracturing or burnt spots, and colour-treated moissanite loses its treatment entirely under torch heat.

Can moissanite prongs be retipped with the stone in place? On untreated moissanite, yes, with careful technique. On colour-treated moissanite, no — torch heat removes the colour treatment, so retipping in place requires a laser welder.