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Cobalt 8mm Promise Ring

Cobalt 8mm Promise Ring

$69.99 USD
$69.99 USD
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Shipping calculated at checkout.
Ring Size

Ring Sizing Guide

Measure at end of day when fingers are slightly larger. Measure 2–3 times for accuracy.

Method 1 — String or Paper

  1. Wrap a strip of paper around the base of your finger.
  2. Mark where the ends overlap.
  3. Measure that length in mm.
  4. Match to the Circumference column below.

Method 2 — Existing Ring

  1. Place a well-fitting ring flat on a ruler.
  2. Measure the inside diameter in mm.
  3. Match to the Diameter column below.
US SizeDiameter (mm)Circumference (mm)
616.551.9
6.516.953.1
717.354.4
7.517.755.7
818.157.0
8.518.558.3
919.059.5
9.519.460.8
1019.862.1
10.520.263.4
1120.664.7
11.521.066.0
1221.467.3
12.521.868.5
1322.269.8
13.522.671.1
1423.072.4

Tip: For wide bands (8mm+) go half a size up for comfort.

Still unsure? Email our jewelers for a personal fit recommendation →
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Scratch-Resistant Tungsten 8mm Ring

Experience the weight and permanence of tungsten — a metal so dense it feels substantial on your finger. This 8mm ring resists scratches and maintains its mirror-bright finish for a lifetime of wear. Tungsten's high density makes it incredibly durable for daily use.

Why Tungsten?

  • Scratch-resistant: Maintains polish indefinitely
  • Hypoallergenic: Safe for sensitive skin
  • Substantial feel: Denser than gold
  • 8mm width: Comfortable everyday wear
  • Forever finish: No re-polishing needed

Perfect for those who value durability over trends. Built to outlast you.

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