Red agate and carnelian are the same thing by different names, and both are sold in Pakistan as surkh aqeeq. It is banded chalcedony coloured by iron oxide, and it has been cut for seals and rings for longer than almost any other gem — Roman intaglios, Mughal seals and the silver rings sold in every bazaar today are all the same material.

The stone

25.15 carats, which is 27.64 ratti. Natural red agate. Rs. 17,600, about Rs. 700 per carat, reference GS-RE-0020. One piece only.

What red agate is, geologically

Agate forms when silica-rich water seeps into a cavity in volcanic rock and deposits layer on layer over a very long period. Those layers are the banding. Where iron oxide is present in the mix, the result is the red to orange-brown range sold as carnelian or red agate. It is cryptocrystalline — made of crystals too small to see — which is why it takes a glassy polish and has no cleavage planes to split along.

Judging one

• Translucency. Hold it against a bright light. Good natural carnelian glows warmly at the edges. Completely opaque material is lower grade; completely transparent is probably glass.
• Colour depth and variation. Some variation across the face is normal and a good sign. Perfectly flat colour is a dye warning.
• Polish. Agate should feel glassy. A waxy or scratchy surface means a rushed cut.
• Shape and symmetry. For a ring, a regular outline keeps the mount simple and the cost down.

Treatment, stated plainly

Red agate is often heated or dyed to deepen its colour. That is the honest position for the stone type and it is what this listing's specification says instead of a blanket claim. Heating carnelian is an ancient and accepted practice — it has been done for thousands of years and the result is stable. Heavy dyeing is a different matter: look for colour pooling inside cracks and a hard line where the colour stops near the base. Our red agate buying guide and dyed and glass aqeeq guide set out the checks.

Can I have it verified?

A certificate of authenticity comes on request and independent laboratory testing can be arranged. Because you pay the rider after the parcel is open, you can also take it to a laboratory of your own choosing inside the seven-day return window.

What can I make with 25.15 carats?

A large men's silver ring in the traditional style, a signet, or a pendant. Shape and measurements have not been recorded for this piece — ask on WhatsApp at +92 308 887 3888 and we will measure it before your jeweller starts.

Care

Agate is 6.5 to 7 on the Mohs scale with no cleavage — forgiving for a ring worn every day. Warm soapy water and a soft brush; no bleach and no ultrasonic cleaner. Water is harmless, so wudu is fine; dry the ring afterwards.

Ordering

Flat Rs. 500 delivery anywhere in Pakistan, insured and tracked, dispatched in one to two working days. Cash on Delivery, seven days to return it unused. More in the red agate collection.

This particular stone

This listing is one natural red agate with a weight of 25.15 Carat. Its price is Rs. 17,600 — roughly Rs. 700 for each carat. Treatment: treatment not tested. Quote reference GS-RE-0020 when you message us about it. The picture is a representative photograph of this type of stone, not of this individual piece, so the stone you receive will differ in its markings and outline. Its weight and price above are this stone's own, and we will send photographs of the actual piece on WhatsApp before you buy.

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.

On the Mohs scale red agate rates 6.5 to 7. 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 red agate 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 red agate 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): Red agate is often heated or dyed to deepen its colour. 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.