2ct Marquise Moissanite Ring, 6x12mm in 925 Silver

At 6x12mm this is a large marquise, and the proportions explain the look. The stone is twice as long as it is wide, which stretches along the finger and covers a lot of skin for its 2ct weight. That length is the draw, and it is also the thing to plan for. A long stone sits best on a long or medium finger, and on a smaller hand it reads as a bold statement rather than a quiet ring.

The stone is moissanite, which suits a large marquise for a practical reason. The narrow points of the cut are its weak spot, and moissanite is hard, at 9.25 on the Mohs scale, so the tips resist chipping better than softer stones would. Its refractive index of about 2.65 is higher than diamond's 2.42, so a stone this size throws a lot of coloured flash. The band is pure 925 sterling silver, which does not tarnish the way brass does.

With one stone size on offer, the choice that matters is ring size. Sizes start at US 4 and rise in half steps, through 4.5, 5, 5.5, 6, 6.5 and further. For a stone this long, err toward the size that fits comfortably over the knuckle, because a tight band tilts the stone and wastes its length. If you are between sizes, go up, and check how the ring moves when your hand is cold.

• Stone: marquise cut moissanite, 2ct, 6x12mm
• Metal: pure 925 sterling silver
• Ring sizes: US 4 upward in half steps
• Setting: claw set solitaire
• Style: statement engagement or wedding ring
• Suits: medium to long fingers