Caring for your stone

At 9 on the Mohs scale, sapphire is harder than everything you are likely to encounter day to day — steel, glass, quartz, sand. Only diamond and other corundum will scratch it. This is why sapphire has always been a sensible choice for a ring worn every day, and why it survives generations.

Cleaning

Warm water, a drop of ordinary washing-up liquid, and a soft toothbrush. Work behind the stone as well as across the top — the film that dulls a sapphire almost always collects underneath, where light enters. Rinse and dry with a lint-free cloth.

Every few weeks is plenty. Skin oils and hand cream are the usual culprits.

Ultrasonic and steam cleaners

Generally safe for an untreated or conventionally heated sapphire in a sound setting. Do not use them if the stone has significant fractures reaching the surface, if it has been fracture-filled, or if you are not certain which. When in doubt, wash it by hand — you lose nothing.

Storage

Store separately, in a soft pouch or a lined compartment. A sapphire tossed into a jewellery box with other pieces will scratch every softer stone it touches — emerald, opal, tanzanite, pearl — and will be scratched in turn by anything harder.

What to keep it away from

• Chlorinated water. Harmless to the sapphire, damaging to gold and platinum alloys over time. Take rings off before a pool or hot tub.
• Household bleach and strong solvents. Same reason — the metal, not the stone.
• Sudden extreme heat. Never take a set stone near a jeweller’s torch without a professional handling it. Thermal shock can crack even corundum.
• Impact on the girdle. Hardness is not toughness. A hard knock on the thin edge of a stone can chip it. Take rings off for the gym and for heavy work.

Setting advice

For a stone you intend to wear daily, a bezel or a half-bezel protects the girdle far better than prongs. If you prefer prongs, six holds more securely than four, and platinum wears more slowly than gold.

For the matched pairs in this collection, tell your jeweller they are a matched pair before work starts — they should be set as a set, with orientation chosen so the colour reads consistently between the two.

Travel and insurance

Carry fine jewellery in hand luggage, never checked. Have any significant stone valued for insurance after purchase — a laboratory report and a purchase invoice together are what an insurer will ask for. Keep both somewhere other than the box the stone lives in.