Topaz & Iolite Ring

Iolite changes colour when you turn your wrist.

Topaz doesn't have to — it already won that argument.

What this ring is

This ring pairs a brilliant-cut blue topaz with a round iolite accent, set on a band of 18ct gold-plated 925 sterling silver. It comes in two sizes, EU 56 and EU 58. House Of The 18th put a stone that shifts colour with the light next to one that holds a single, steady blue.

What is blue topaz?

Topaz is a naturally colourless aluminium silicate mineral. This stone's blue comes from irradiation and heat treatment, the standard process behind nearly all blue topaz on the market. It rates 8 on the Mohs scale, among the more durable stones House Of The 18th works with.

What is iolite, and why does it look different from different angles?

Iolite is the gem form of cordierite, and it's strongly pleochroic — meaning it shows different colours depending on the angle it's viewed from, shifting between violet-blue and a smoky grey-yellow. This optical effect is natural to the mineral and isn't a result of treatment. Iolite rates 7 to 7.5 on the Mohs scale.

Why set a colour-shifting stone next to a fixed one?

Topaz gives the ring one dependable colour from any angle. Iolite gives it a second colour that only shows up when the hand moves. House Of The 18th set them together so the ring reads differently depending on whether it's still or in motion.

How to care for topaz and iolite

Both stones are hard enough for daily wear, but should still be removed before contact sports, manual work, or ultrasonic cleaning, which can stress faceted stones over time. Clean with a soft cloth and avoid harsh chemicals, which can dull the plating around the settings.

Specifications

Frequently Asked Questions

Is the topaz on this ring natural or treated? The topaz is irradiated and heat-treated to reach its blue colour, which is standard practice across nearly all blue topaz sold commercially and is not the stone's original colourless state.

What is iolite and is it treated? Iolite is a naturally pleochroic gemstone, meaning its colour genuinely shifts with viewing angle, and it is rarely treated, unlike many of the other coloured stones in this collection.

What does 18ct gold-plated mean? 18ct gold-plated describes a thin layer of 18-carat gold applied over the 925 sterling silver base, referring to the gold's purity rather than the ring's overall carat weight.

How durable is this ring for daily wear? Both stones rate 7 to 8 on the Mohs scale, making this one of the more durable rings in the collection and well suited to daily wear with normal care.

Can this ring be stacked with other rings? Yes, and it's available in EU sizes 56 and 58 to fit alongside other pieces in a stack.