Category: Gemstones Basics

Discover the legendary histories of famous diamonds like the Koh-i-Noor and Hope Diamond. Learn about their origins, famous owners, recutting, and settings in crowns and jewelry. Essential knowledge for jewelry professionals and designers seeking inspiration from these iconic gemstones.

This guide details the world’s largest rough diamonds over 400 carats. Discover giant stones like Sewelô (1758 ct) from Botswana, Lesotho’s Legend (910 ct), and Sierra Leone’s Star (969.8 ct). Learn about their discovery in mines, cutting into polished gems, D color, high clarity, and famous buyers. Essential for jewelry professionals sourcing exceptional diamonds for custom designs and retail.

このガイドでは、100カラットを超える世界最大級のダイヤモンドについて詳しく解説します。鉱山での発見、カリナンのような有名な宝石のカット、そして重量、色、透明度に関する重要な詳細を網羅し、宝石のプロやデザイナーが特別な石を調達する際に役立ちます。

Diamond value is based on “4C” standards: Color, Clarity, Cut, Carat Weight. Major labs like GIA and China’s GB/T 16554 use this. It determines price, rarity, and beauty for jewelry businesses and sellers.

Learn how to spot real diamonds. This guide shows key tests for luster, fire, and using a thermal tester. Identify natural vs. synthetic diamonds like HPHT and CVD, and tell them apart from fakes like cubic zirconia. Essential for jewelry professionals to verify authenticity.

ダイヤモンドは地中深くの高温高圧下で形成され、キンバーライトのような特殊な火山岩によって地表に運ばれます。主な産地はロシア、ボツワナ、カナダです。このガイドでは、宝石のプロ向けに、ダイヤモンドの地質学的起源と世界的な分布について解説します。