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Noraleaf Lab-Grown Purple Sapphire Engagement Ring in Black Ruthenium

Regular price $185.00 $155.00 16% off
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Size Chart

Find your ring size

  1. Print at 100% / Actual Size — turn off "fit to page" or scaling.
  2. Check the printed ruler measures exactly 80 mm.

Method A — Measure a ring

Lay a ring you own over the circles. The matching circle is your size.

Method B — Finger strip

Cut out the strip, wrap it around your finger, thread the end through the slit, and read your size.

Open the printable sizer (PDF)
1. Calibrate your screen — pick a reference object, hold it against the outline, and drag until the widths match exactly. On a phone, a coin is easiest — a card is often wider than the screen.
Bank card — hold vertically
2. Match a ring you own — drag until the circle fits just inside one of your rings.
US 6 · 16.5 mm · UK L½ · EU 52

This on-screen tool is a close guide, not a guaranteed exact fit. For certainty, order a ring sizer.

US Diameter Circumf. UK/AU/IE EU

UK, Australia & Ireland share the letter system. European sizes are approximate conversions.

In Stock Free Delivery Est. Sep 5

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Noraleaf Marquise Moss Agate Engagement Ring in Black Ruthenium by Aquamarise, worn on the hand of a model with dark green nails.

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The same charcoal-gunmetal finish across engagement rings, stacking bands and matching sets — every one plated over solid 925 sterling silver. Shopping for him? Our men’s black rings add tungsten and titanium, which hold their color harder than any plating.

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Free U.S. Shipping + Worldwide Delivery

Ethically Sourced Gemstones

Handcrafted by Aquamarise®

Complimentary Engraving on Every Order

Free U.S. Shipping + Worldwide Delivery

Ethically Sourced Gemstones

Handcrafted by Aquamarise®

Complimentary Engraving on Every Order

What Makes Aquamarise® Different

Rutilated Quartz & Meteorite Couples Ring Set by Aquamarise, matching women's and men's rings

Ethically Sourced, Always

Each gemstone is meticulously hand-selected for its brilliance and clarity, responsibly sourced from trusted partners around the world.

Built to Be Worn, Not Just Admired

Every piece is expertly crafted and finished to endure daily wear, combining lasting strength with enduring beauty beyond the display case.

Specifically Designed for You

Every Aquamarise® creation is thoughtfully designed for those who view jewelry as a personal expression. Never mass-produced, each piece carries a sense of meaning and individuality.

Crafted to Last. Not Just Sparkle.

While most jewellers focus on appearance, Aquamarise® focuses on craftsmanship, durability, and pieces you will treasure forever.

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Personalized Engraving
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Frequently Asked Questions

Ruthenium is a platinum-group metal — the same family as platinum, palladium and rhodium — and one of the rarest elements in the earth’s crust. It is extremely hard but also brittle, which is why it is used as a finish rather than a solid metal: here it is electroplated over a solid 925 sterling silver base and tuned toward a smoky, near-black tone.

Despite the name it is not a flat jet black. It reads deep charcoal in daylight and near-black in low light, which is what makes stones and carved detail feel dimensional. Our full guide, What Is Black Ruthenium?, covers the science — or browse the whole black ruthenium collection.