4.00 CT Oval Opal Cabochon Couture Ring in 14kt White Gold and 14kt Yellow Gold.

This two tone opal ring sets a 4.00 carat oval opal cabochon in a white gold halo of round diamonds, on a shank of 14kt yellow gold. The 26 diamonds add 0.90 carats, for 4.90 carats of gemstones in all. The ring is a size 7 and weighs 8.3 grams. Everything below describes this exact ring, which you can see and try on at our Boca Raton showroom.

The two tone opal ring at a glance

Here are the specifications of this two tone opal ring, as recorded for this piece.

At the center is an oval opal cabochon of 4.00 carats, held in prongs. Our listing records its color as blue and green, and its clarity as Excellent.

Around it is a halo of 26 round brilliant cut diamonds of about 0.038 carats each, 0.90 carats in total, graded I color and SI1 clarity.

The mounting combines two metals: the head that holds the opal and the diamonds is 14kt white gold, and the shank is 14kt yellow gold. The ring is a size 7 and weighs 8.3 grams. It can be sized to fit.

In short, this two tone opal ring pairs a large, lively blue-green opal with a bright diamond frame and a warm gold band, a combination that looks different from every angle.

Is the 4.90 carats one opal?

No, and it is worth being clear. The 4.90 carats is the total weight of every stone in the ring, not the weight of the opal.

The oval opal is 4.00 carats. The 26 diamonds in the halo add 0.90 carats. Together they make 4.90 carats of gemstones.

Opal is a light gem, less dense than sapphire or diamond, so a 4 carat opal ring carries a stone that looks larger than a faceted gem of the same weight would. On the hand this one fills the head generously.

A blue green opal ring

The stone in this blue green opal ring shows broad flashes of turquoise, green and deeper blue across a pale, translucent body. Tilt the hand and one color gives way to another; hold it still and the whole face seems to glow from inside.

That effect is called play-of-color, and it is what separates opal from every other gem. It comes from the structure of the stone: opal is built from microscopic spheres of silica packed in an orderly pattern, and light passing between them splits into spectral colors. The Gemological Institute of America explains how that structure works.

Blue and green are the most common play-of-color hues, and in a stone this size they cover a large area, which is what makes a blue green opal ring so striking from across a table.

Our listing records the clarity of this opal as Excellent, meaning a clean, translucent stone with little matrix to interrupt the color. The written appraisal describes it in detail.

Why two metals?

A two tone opal ring is a deliberate design choice, not a compromise. White gold around the stones keeps the diamonds looking bright and white and gives the opal a cool, neutral frame. Yellow gold on the shank adds warmth where it touches the hand.

There is a practical side as well. Yellow gold is not plated, so the part of the ring that takes the most rubbing against the finger keeps its color without maintenance. White gold is usually finished with rhodium for a bright white surface, and confining it to the head means less of the ring needs re-plating over the years.

Visually, the split does something useful too. From above you see white gold and diamonds around the opal; from the side, a warm gold band. The ring changes character depending on how you look at it, which suits a stone that already does the same.

A two tone opal ring is also easy to wear with a mixed jewelry box. It sits comfortably next to both yellow and white gold pieces, so it does not force the rest of your jewelry into one camp.

An oval opal cabochon ring

Almost every opal you see is cut as a cabochon: a smooth, domed top with no facets. An oval opal cabochon ring follows the oldest way of cutting this gem, and there is good reason for it.

Faceting works by bouncing light off flat internal surfaces, which suits a transparent stone like diamond or sapphire. Opal's beauty comes from inside, so a polished dome shows it better than facets would.

The dome also gathers the play-of-color into one glowing face. As you tilt an oval opal cabochon ring, the color sweeps across the curve rather than jumping from facet to facet.

There is a practical benefit as well. Opal is a softer gem, and a domed surface with no sharp corners is less likely to chip in everyday wear.

A 4 carat opal ring with a diamond halo

The halo around this stone is a close ring of small diamonds set right against the cabochon. In a 4 carat opal ring, that frame does two things.

First, it draws a bright white line around the opal, which separates the blue-green from the metal and makes the color read more clearly. Second, it adds sparkle: opal glows but does not flash the way a faceted stone does, and the diamonds supply that contrast.

Each diamond is held in its own prongs rather than in a channel, so light reaches more of every stone. From the side you can see the row of prongs running around the head like a crown.

At 0.90 carats across 26 stones, the diamonds in this 4 carat opal ring are sized to support the opal rather than compete with it. They are graded I color, a near-colorless grade, and SI1 clarity, meaning small inclusions that are typically not visible to the eye.

About opal

Opal is hydrated silica: silica with water held inside its structure, usually between three and ten percent. That water is part of what gives opal its glow, and part of why it needs a little more care than harder gems.

Most of the world's fine opal comes from Australia, where the opal fields of New South Wales and South Australia have supplied the majority of the market for more than a century.

Opal ranks about 5.5 to 6.5 on the Mohs hardness scale, softer than sapphire or diamond. Worn thoughtfully it lasts beautifully, and antique opal rings survive in fine condition all the time, but it is jewelry to enjoy rather than jewelry to forget about.

Opal has been prized since antiquity. Roman writers valued it for showing the colors of many gems in one stone. The old superstition that opal brings bad luck comes from a nineteenth century novel, not from any tradition among jewelers.

Opal is one of the birthstones for October, alongside tourmaline, and it is the traditional gift for a 14th wedding anniversary.

Solid opal, doublets and triplets

Opal is sold in three forms, and the difference matters. A solid opal is a single piece of natural opal, cut and polished on its own. A doublet is a thin slice of opal backed with a darker layer to deepen the color, and a triplet adds a clear cap on top.

The stone in this two tone opal ring is a solid opal cabochon, set in prongs so you can see it from the side as well as from above. Doublets and triplets are normally set in closed bezels, because their layered edges have to be hidden.

That difference matters in care as well. Doublets and triplets should not be soaked, because water can work its way between the layers. A solid opal has no layers to separate.

Solid opal also holds its value better, and it is what most people picture when they think of an opal ring.

An opal statement ring

With a 4 carat center and a full diamond halo, this is an opal statement ring in the proper sense: the one piece you wear when everything else stays quiet.

An opal statement ring works particularly well in the evening, because opal responds to changing light. Candlelight, lamplight and the movement of a room bring out different flashes in the stone.

It is just as good in daylight, where the blue and green look fresh and bright rather than formal. Worn on the right hand with a slim chain and simple earrings, an opal statement ring carries a whole outfit.

Blue-green is also an unusually easy color to dress around. It sits well with navy, white, cream, denim and gray, and the yellow gold band keeps it from feeling cold.

Who a two tone opal ring suits

A two tone opal ring suits someone who wants a colored stone with character rather than a conventional gem. Opal is not graded on a simple scale the way a diamond is: you choose it because you like the particular pattern of color in that one stone.

It also suits anyone who wears both yellow and white gold. Many people end up with a jewelry box that mixes the two and then hesitate over which metal a new ring should be. A two tone opal ring sidesteps that question entirely.

And it suits October birthdays and 14th anniversaries, where a 4 carat opal ring with a diamond halo makes a considerably more memorable gift than a small birthstone piece.

Can an opal be an engagement ring?

It can, and opal engagement rings have a long and romantic history. But it is worth being honest about the trade-off first.

At 5.5 to 6.5 on the Mohs scale, opal is softer than the stones usually chosen for daily wear, and it is sensitive to knocks and to sudden changes in temperature or humidity. An engagement ring is typically worn every day, including while cooking, cleaning and traveling.

If you love opal and want it on your left hand, treat it as a ring you take off for chores, sport and gardening. Plenty of people do exactly that and wear their opal for decades.

If you would rather not think about it at all, a sapphire or diamond center is the more practical choice, and we can show you both alongside this ring.

Choosing a two tone opal ring

When you compare a ring like this, start with the play-of-color. Look at the opal from several angles and in different light. The best stones show broad flashes that cover most of the face, rather than a patch of color in one corner.

Next, look at the diamonds. The halo should be even all the way around, with the small stones level in their prongs and the metal between them neat.

Then consider the two metals. In a well-made two tone opal ring the join between white and yellow gold is clean and intentional, and the proportions look balanced rather than accidental.

Finally, put it on. Opal is the gem that changes most between a photograph and real life, and seeing the color move on your own hand is the only way to judge it. The right two tone opal ring is usually the one whose stone you keep looking back at.

Caring for your opal ring

Opal deserves a little more attention than a harder gem, and the rules are simple.

Clean the ring in warm, not hot, water with a drop of mild dish soap, brush gently around the halo with a soft toothbrush, rinse and pat dry. Our jewelry care guide has more detail.

Never put an opal in an ultrasonic or steam cleaner. Both can damage the stone, and heat is the main thing to avoid: keep the ring away from hot water, long periods of direct sun and very dry air, all of which can cause the fine cracks known as crazing.

Take it off for the gym, gardening, cleaning and swimming, and store it away from harder stones so nothing scratches the cabochon. Have the prongs checked from time to time. We offer complimentary cleaning and inspection for jewelry bought from our store.

Seeing this two tone opal ring in Boca Raton

Opal is the gem that photographs least well, because a still image can only capture one angle of the play-of-color. You are welcome to try this two tone opal ring on at our Boca Raton showroom and watch the blue and green move for yourself.

We are open Monday to Friday, 9:30 to 5:30, and Saturday, 10:30 to 4:30. Directions are on our Visit Us page.

David Stern Jewelers has served Boca Raton for over 40 years. David Stern is a GIA Graduate Gemologist, so detailed questions about the opal and the diamonds can be answered on the spot.

Sizing, appraisal and insurance

This ring is a size 7 and can be sized to fit. The yellow gold shank is plain, so there is metal to work with, and we confirm before any work is done.

It includes a written jewelry appraisal by David Stern, which describes the opal, the diamonds and the gold and gives a replacement value for insurance.

More opal jewelry

See our oval opal halo ring in white gold, our opal doublet pendant, or browse all our rings.

Questions about this two tone opal ring