Opal — The only stone that contains all the colors of the spectrum

Opal is the only gemstone whose color is born from light itself—not from a pigment, but from a diffraction phenomenon that gemmologists call play-of-color. Boulder opal, white opal, bad-luck myth: ...

Tourmaline — A Stone of a Thousand Colors

Tourmaline is one of the most fascinating gemstones—not for a single color, but for every color at once. Rubellite, indicolite, Paraíba, watermelon tourmaline: each variety tells a unique chemical ...

Tanzanite — a stone born from a single mountain, the rarity of Kilimanjaro

A stone born from a single mountain, on the edge of the Great African Rift. Tanzanite is perhaps the most unlikely of the natural gemstones — and one of the most captivating.

Choosing a gemstone by its color — what each shade says about you

Blue, green, purple, red, yellow: the color of a natural gemstone is no coincidence — it is its mineral signature and its first conversation with you. A guide to choosing by resonance.

Sunstone: the gem that captures the light

There is something immediately generous about sunstone. As soon as light touches it, thousands of copper-colored flashes streak through the gem — as if it held a small reserve of summer sunshine de...

Citrine — a sunstone that warms the heart

Citrine is one of the few stones whose color is universally admired without effort. Pale yellow, deep golden, warm amber—it captures the light as if it were made of nothing else. Behind this lumino...

Labradorite: the stone that carries light within it

Labradorite is one of the few gemstones that changes with every glance. Electric blue, deep green, warm gold — its reflections never repeat. Discover the fascinating history of this stone of the No...

Care for 925 Silver Jewelry & Gemstones — Orcha Jewelry Guide

Your 925 sterling silver and gold jewelry, set with natural gemstones, deserves special care to retain its brilliance over time. Silver oxidizes when exposed to air and moisture, while some stones ...

How to Identify a Quality Gemstone — Orcha Jewelry Guide

Not all natural gemstones are created equal—even within the same species. Two pink tourmalines can have very different prices depending on their color, transparency, and cut quality. Understanding ...

Find your ring size: online ring size chart and size conversions by country

Here we explain how to easily measure your finger size. Online ring sizer and size correspondences by country.