Questions

No — moissanite is its own gemstone, lab-created silicon carbide, with more fire than a diamond (dispersion 0.104 versus 0.044) and a hardness of Mohs 9.25. Every moissanite stone of 0.1 ct and over ships with a GRA certificate for the stone; below that no stone certificate is issued, and each product page says which it is. The color and clarity grades we quote are the maker’s. It costs a fraction of a mined diamond. We never describe moissanite as anything but moissanite. The full comparison is in our guide, Is Moissanite a Real Diamond?

On a basic thermal tester, yes — moissanite conducts heat much the way a diamond does, so pen testers often read it as diamond. A dual moissanite/diamond tester tells them apart. We mention this only so you are never surprised: we always describe the stone as moissanite. The tests that do and do not work at home are in our guide, How to Tell Moissanite from a Diamond at Home.

Every moissanite piece, and every sterling and pearl gift, is 925 sterling silver, 92.5% pure; the moissanite pieces carry a platinum plating on top. Those pieces are never plated over brass and never gold-filled, and none is solid gold or vermeil. The gift sets and the men’s chains are plated eco-brass, and their pages say so. Sterling is a genuine precious metal, soft enough to be worked finely and hard enough to wear daily. We go further on the metal in our guide, Is Sterling Silver Good for a Moissanite Ring?

It can, slowly, with exposure to air and skin — that is the metal living, not a fault. A soft polishing cloth brings it back to bright, and storing pieces dry and sealed slows it right down. See our care guide for the full routine, or our journal guide, How to Care for Moissanite and Sterling Silver Jewelry.

Nearly every ring we sell is made on an adjustable band, so there is no size to choose. The Eclipse Eternity Band is offered in US sizes 6, 7 and 8. For that one, or to check your size anyway, use the ring-size converter in our Sizing Studio: measure the inside circumference of a ring you already own, or wrap a strip of paper around your finger and measure it in millimetres, and the tool gives you your US size instantly. Change-of-mind returns are not offered, and a wrong size ordered is not covered, so check your size before you order.

Shipping is $8.99 to 100+ countries, fully tracked, and free on any order over $150 (judged on your total after any discount) — the threshold is on your cart total, so two smaller pieces can cross it together. Delivery is counted from when you place the order, and the 1–3 business days of preparation sit inside that window rather than being added to it: typically 5–8 business days to the U.S., U.K. 5–8, Europe 4–10, Canada 7–10, Australia 5–10, and elsewhere 7–14. Those are estimates, not guarantees. Every order ships duties-paid (DDP), so nothing should be asked of you on delivery; if a carrier ever presents a charge, write to hello@maisonnoctaura.com before paying it. Every order is covered by our 7-Day Arrival Guarantee: if a piece arrives damaged, defective, or not what you ordered, email us within 7 days of delivery with your order number and clear photos for a free replacement — or a refund if we cannot replace it, at no cost to you. We don’t offer change-of-mind returns, and we’d rather tell you that here than after you buy. Full details are on our Shipping and Returns pages.