Opal pricing confuses more buyers than any other gem we sell, because two stones of the same weight can differ in price by six or seven times. This is the largest Ethiopian opal in our collection and it carries the lowest rate per carat, which makes it the clearest place to explain what is actually going on.

This stone's numbers

25.65 carats, which is 28.19 ratti. Rs. 30,750, about Rs. 1,199 per carat, reference GS-000730. Recorded shape: oval. Origin: Ethiopia. One piece — the photograph is of the stone you would receive.

Why the rate per carat varies so much

Across our Ethiopian opals the rate runs from about Rs. 1,199 per carat here to roughly Rs. 8,274 on the dearest — nearly seven times, in the same gem from the same source. Two things drive it. The first is the play of colour: how much of the stone flashes, how bright those flashes are, and how many colours appear. The second is size, and it works backwards from what people expect. Large clean opal is not rare in the way large clean sapphire is, so a big stone spreads its cutting cost over more carats and the rate falls.

Measured from the photograph, play of colour covers about 11% of this stone's face, and the body reads at a brightness of 199 out of 255 — a bright, light body. That is a good showing for a stone of this size, and at just under Rs. 1,200 per carat it is the most opal you can get from us for the money.

What a fair quote looks like in Pakistan

• Light play, small stone: roughly Rs. 1,000 to Rs. 3,000 per carat.
• Good broad play across the face: roughly Rs. 3,000 to Rs. 9,000 per carat.
• Exceptional, dense, multi-coloured play: above that, and it climbs steeply.
• A large, intensely flashing opal for a few hundred rupees per carat is resin, doublet or a lab-grown imitation. Nothing else explains the price.

The water question — read this before you buy

Ethiopian opal is usually hydrophane, meaning it is slightly porous and will absorb water. When it does, it can turn clear or cloudy and the play of colour may fade for a while. This is not damage and it is not a fault in the stone: as it dries, the colour comes back. Let it dry slowly at room temperature and never try to speed it up with heat. Keep it off while washing, swimming or doing wudu, and keep it away from oils and perfumes, which it will also drink in and which do not simply evaporate.

Treatment

We have not had this stone tested, and the specification sheet says exactly that rather than claiming better. The treatment worth knowing about in this material is smoke treatment, which darkens a pale body to imitate the far more valuable dark-bodied opals. This stone has a bright, light body and shows no sign of it, but we would rather tell you the test has not been done. Independent laboratory testing can be arranged before dispatch — ask us and we will organise it.

Durability

Opal rates 5.5 to 6.5 on the Mohs scale, which is softer than most gems people wear daily. It wants a protective setting, and it does not belong in an ultrasonic or steam cleaner. Wipe it with a soft dry cloth. Turn any opal under a light and look for fine surface cracks, called crazing — a sound, well-domed cabochon is worth considerably more than a flat or cracked one.

Read further

Our Ethiopian opal price guide goes into the rates in detail, the general price guide puts opal alongside other stones, and the opal buying guide covers what to inspect. The rest of the range is on the Ethiopian opal page.

Ordering

One piece only. Flat Rs. 500 delivery anywhere in Pakistan by insured, tracked courier, dispatched in one to two working days. Cash on Delivery — open the parcel and look at the stone before you pay — and seven days to return it unused. Dimensions have not been recorded; message us on WhatsApp at +92 308 887 3888 and we will measure it before you order.

This particular stone

This listing is one natural ethiopian opal with a weight of 25.65 Carat. Its price is Rs. 64,130 — roughly Rs. 2,500 for each carat. Origin: Ethiopia. Treatment: treatment not tested. Quote reference GS-000730 when you message us about it. The photographs show this exact stone, so what arrives at your door is the piece you chose on screen.

Above twelve carats you are into collector territory. Pieces this heavy are usually set as pendants or kept loose, and they are prized for the size of rough they came from. If you do set it, choose a bezel or a heavy claw to protect the edges.

Whoever you buy ethiopian opal from, make sure of three things: the stone is natural rather than lab-grown, glass or glass-filled; any treatment is stated in writing; and the weight quoted is the weight of the finished stone. We check every ethiopian opal for those three points before it is listed, a certificate is available on request, and because you pay on delivery you can look at the stone — or have it tested — before any money changes hands.

We sell natural stones only and inspect each one before it is listed. Treatment for this stone: Treatment not tested. Certificate available on request. As general background (not a statement about this stone): Solid opal is usually untreated; some opal is smoke- or sugar-treated, and doublets/triplets exist — we sell solid natural opal. Ask us on WhatsApp and we will tell you what we know about this exact stone; independent lab testing is available on request.

A certificate of authenticity is available on request for this stone, and independent laboratory testing can be arranged. Because you pay on delivery, you can also take the stone to a lab of your choice within the 7-day return window. Read more on our authenticity page.