💍 Ring Size Guide

Australian ring sizes use the UK letter system. Find your size below, or measure the inner diameter of a ring that fits.

UK / AUSUSEUDiameter (mm)
H44715.7
I4.54816.1
J54916.5
K5.55016.9
L65117.3
M6.55217.7
N75418.2
O7.55518.6
P85619.0
Q8.55719.4
R95819.8
S9.55920.2
T106020.6
U10.56221.0
V116321.4
W11.56421.8
X126522.2
Z136723.0
💡 Not sure? Geoff resizes rings up to 3 UK sizes up or down after purchase — just let him know when you order. If you're between sizes, go up.
Ring resizing available up to 3 UK sizes — just contact Geoff after purchase

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One of the last opal triplet cutters in the world

Natural Australian Opals, Cut by Hand

50 years of passion in every stone. Geoff is one of the last people on earth still cutting opal triplets — genuine Australian opals, cut in Melbourne and direct from the source to you.

Browse the Collection → Read Geoff's Story
Ladies opal triplet ring with diamonds — cut by Geoff in Melbourne
Ladies Diamond & Opal Ring
Mens opal triplet ring — cut by Geoff in Melbourne
Men's Cushion Ring
Mens oval opal triplet ring — cut by Geoff in Melbourne
Men's Oval Ring
1975cutting opals since
50+years of craft
100%natural Australian opal
⭐
5.0 / 5 Rating
3,800+ verified reviews
🇦🇺
100% Australian
Natural opals, never synthetic
📦
Free Worldwide Shipping
Insured & tracked, every order
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Ring Resizing
Up to 3 UK sizes — just ask Geoff
The bloke behind the stones

50 Years of Opal. One Lifetime of Passion.

Geoff from Rainbow Rock Opals with a fresh catch
Est. 1975 Melbourne, VIC

From a Garage in Melbourne to Opal Lovers Worldwide

Geoff started cutting opal for a living over 50 years ago. What began as a fascination quickly became a lifelong passion — he's been involved in every corner of the trade, from mining rough opal at White Cliffs to cutting, polishing, and setting each stone himself.

At just 18, he left his day job and set up shop in his dad's garage right here in Melbourne. Things took off fast — within a couple of years, he had a dozen full-time cutters working alongside him, supplying loose stones to jewellers and wholesalers around the world.

Then came the retail outlets, the one-of-a-kind pieces, and decades of supplying opal lovers around the world. After 30+ hectic years (and a global financial downturn), Geoff decided it was time to downsize and go fishing more. These days, he still gets just as excited cracking open a new parcel of rough opal as he did all those years ago.

Cheers, Geoff 🎣
50+
Years of Craft
1975
Cutting opals since
5.0★
Average Rating
The collection

Handcrafted Opal Jewellery

Every piece features a natural Australian opal, cut and set by Geoff in Melbourne. Each one is one of a kind.

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Geoff's speciality

What Is an Opal Triplet?

A triplet is the pinnacle of the opal cutter's craft — three precision layers fused into one stone that blazes with colour. Almost nobody still makes them.

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Three Layers, One Stone

A triplet is built from three layers: a clear glass backing, a wafer-thin slice of natural opal with one side sprayed black to make the colours fire, and a clear quartz cap on top. Each layer must be precision-fitted — the slightest misalignment ruins the stone.

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Why the Colour Blazes

Spraying the back of the opal slice black makes the colour fire jump out dramatically — far more vivid than you'd see in a solid stone of the same quality. The quartz cap then magnifies and protects it. The result is a stone that looks like it's lit from within.

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Built to Last a Lifetime

The quartz cap makes triplets extremely hard and scratch-resistant — far tougher than an exposed solid opal. Geoff backs every triplet with a lifetime guarantee against delamination from water damage. If it ever separates, he'll replace the stone free of charge.

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A Dying Craft

Cutting triplets requires years of practice, extreme patience, and a feel for the stone that can't be taught from a book. The opal slice must be ground to less than 1mm thick without cracking — get it wrong and the stone is ruined. Geoff is one of a very small handful of people in the world still doing it.

What our customers reckon

Loved by Opal Enthusiasts Worldwide

★★★★★
"Went out of his way to do an exchange and resizing for me. 10/10 customer service and such a gorgeous ring. Amazing craftsmanship."
Verified Buyer
Men's Opal Ring — Sterling Silver
✓ Verified Purchase
★★★★★
"Love the gems, always great quality. Been buying from him for a while now. His rapid responses and updates on shipping is also a plus. 10/10"
Julian
Men's Opal Ring — Sterling Silver
✓ Repeat Customer
★★★★★
"So great, looks incredible in person. Couldn't recommend Geoff enough."
Rachel M.
Opal Pendant — 14ct Yellow Gold
✓ Verified Purchase
★★★★★
"As always, very gorgeous opals. Highly recommend!"
David C.
Men's Opal Ring — Sterling Silver
✓ Repeat Customer
★★★★★
"Crazy good quality and simply magnificent! The photos don't do these stones justice — they're even more stunning in real life."
Martin
Natural Opal Collection
✓ Verified Purchase
★★★★★
"Geoff is a true craftsman. You can tell these pieces are made with decades of experience and real love for opals. Will be back for more."
Verified Buyer
Women's Opal Ring — 14ct Gold
✓ Verified Purchase
Good to know

Common Questions

An opal triplet is made of three layers: a clear glass backing, a wafer-thin slice of natural Australian opal with one side sprayed black to intensify the colour, and a clear quartz cap on top. The black spray makes the colour fire blaze dramatically, while the quartz cap protects and magnifies it.
Yes — opal triplets are far more durable than solid opals for daily wear. The hard quartz crystal cap protects the opal surface from scratches. Geoff backs every triplet with a lifetime guarantee against delamination.
Yes — free insured worldwide shipping on every order. All pieces are tracked from Melbourne, Australia right to your door.
Yes — Geoff offers ring resizing up to 3 UK sizes up or down. Just contact him after purchase with your size and he'll sort it out. For adjustments beyond 3 sizes, get in touch for a quote — larger changes may not always be possible as the ring can distort.
Mens opal rings typically feature larger, bolder stones in heavier sterling silver settings. Womens rings tend toward more delicate settings, often with diamond accents, in sterling silver or 14ct gold.
Caring for your piece

How to Look After Your Opal

Opal triplets are hardwearing for everyday wear — but a little care goes a long way to keeping them brilliant for life.

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Avoid Chemicals
Remove rings before applying perfume, moisturiser, cleaning products or hand sanitiser. Chemicals can dull the finish over time.
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Avoid Chlorine & Salt Water
Everyday water is fine — you can shower in your opal jewellery. Avoid prolonged exposure to chlorinated pools or salt water, which can affect the setting over time.
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Store Away from Heat
Avoid leaving opals in direct sunlight or hot cars for extended periods. Extreme heat can cause the stone to dry and crack.
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Clean Gently
Use a soft, slightly damp cloth to clean your piece. Never use ultrasonic cleaners or harsh jewellery solutions on opal triplets.
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Store Separately
Keep your opal piece in its own pouch or box. Harder stones in the same drawer can scratch the quartz surface over time.
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Lifetime Guarantee
Geoff backs every opal triplet with a lifetime guarantee against delamination — the layers separating. Just get in touch if you ever have an issue.

Questions About a Piece?

Geoff knows these stones inside out — if you want to know more about a particular piece,
the opal, or how it was made, he's genuinely happy to chat.

Get in Touch

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