The Curator's Journal

Emerald Oil & Clarity Enhancement: No-Oil, Minor, Moderate Explained

Almost every emerald you will ever see has been oiled — and that is neither a secret nor a scandal. It is the oldest and most accepted enhancement in the gem world. What separates a fine emerald fr...

Heat Treatment in Coloured Gemstones: Disclosure & Why It Isn't a Flaw

Few words on a gemstone report carry as much weight — or as much misunderstanding — as "heated." Heat treatment is the most common enhancement in the coloured-stone world, it is centuries old, and ...

How to Read a GIA Coloured-Stone Report

For a fine coloured gemstone, the laboratory report is the document that protects its value — and the GIA coloured-stone report is the one the trade trusts most. But a report is only useful if you ...

GIA's 2026 Coloured-Stone Report Changes: What They Mean for You

The document that protects the value of a fine coloured gemstone is its laboratory report — and on 1 January 2026, the most trusted of those, the GIA coloured-stone report, was redesigned and its o...

Morganite vs Pink Sapphire vs Kunzite: Choosing a Pink Stone

Pink is having its moment, and three lovely gems compete for it — each with a different temperament. The right choice depends almost entirely on the piece: a ring you'll wear every day asks for som...

Aquamarine vs Blue Topaz vs Blue Zircon: A Curator's Guide

Three gems can all wear a beautiful blue — and they could hardly be more different underneath. One is a precious, durable classic; one is an abundant, vivid, treatment-born favourite; one is a bril...

Tsavorite vs Emerald: The Green That Needs No Oil

Green has one legendary name — emerald — and one quiet challenger that surprises everyone who meets it: tsavorite. Discovered in East Africa and brought to the world in the 1970s, tsavorite is a gr...

Red Spinel vs Ruby: The Connoisseur's Comparison

For most of history, the two were the same stone. The "Black Prince's Ruby" in the British Imperial State Crown and the "Timur Ruby" are both, in fact, spinels — celebrated as rubies for centuries ...

Padparadscha vs Pink-Orange Sapphire: What the Certificate Must Say

Few gems are as quietly coveted — or as widely misunderstood — as the padparadscha. Named for the lotus blossom, it is the delicate marriage of pink and orange in a single sapphire, and it sits amo...

Madagascar vs Ceylon Blue Sapphire: A Curator's Comparison

Two of the finest blue sapphires you can buy come from opposite ends of the gem world's history: Ceylon, the storied island source celebrated for centuries, and Madagascar, the great modern deposit...