Opal in the trade comes with a standard set of caveats, and an honest dealer mentions them before you pay. Solid opal is usually sold in the state in which it was mined, but some stones are smoke-treated or sugar-treated, and doublets and triplets appear among solid stones. GemStore sells solid natural opal only, and independent lab testing can be arranged if you want paper evidence.

About this exact stone: it is a natural black fire opal of 3.75 carats, SKU GS-000725. The price is Rs. 12,380, about Rs. 3,301 per carat. Everything else you should check for yourself in the photographs and, if you wish, in a short video requested over WhatsApp.

Wear it carefully. Opal rates 5.5 to 6.5 on Mohs and can scratch or crack from heat and sudden changes in temperature. A pendant suits it well; a ring should have a protective bezel.

Cash on Delivery lets you open the parcel and look before you pay. See other options in the opal collection.

Pay Cash on Delivery once you have opened the parcel and seen the stone yourself, anywhere in Pakistan, with 7 days to return it if you change your mind. Before you choose, read our opal guide.

This particular stone

This listing is one natural opal with a weight of 3.75 Carat. Its price is Rs. 12,380 — roughly Rs. 3,301 for each carat. Treatment: treatment not tested. Quote reference GS-000725 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.

Between two and six carats is the range most people choose for a gents' ring or a noticeable pendant. Here colour drives the price more than size does, which is why two stones of near-identical weight can be priced very differently.

On the Mohs scale opal rates 5.5 to 6.5. That is middle-of-the-road hardness: comfortable in pendants and earrings, and in rings worn with some care. Store it apart from harder stones so it does not pick up scratches, and wipe it with a damp cloth rather than scrubbing.

Whoever you buy 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 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.