The Curator's Journal

The Perfection of Peridot, part 1: A Glorious Green Gem

Species Forsterite Olivine var. Peridot Chemical Formula Mg2SiO4 w/ Fe2+ and/or Fe3+ Mohs Hardness 6.5 - 7  Cleavage Poor Luster Greasy to Vitreous Refractive Inde...

The Splendour of Spinel, part 6: A Recent Return

Spinel now holds an important place in the world of bespoke gemstone jewellery, but for a large portion of history the stone was underappreciated. Advances in the laboratory and changes in the land...

The Splendour of Spinel, part 5: Mysterious Marvels

The spinel mines of central Asia produced many of the world's greatest spinels, and by extension some of history’s greatest “rubies”, but among the world’s most prized “ruby” and spinel gemstones a...

The Splendour of Spinel, part 4: Tajik Treasures

During the centuries in which the spinel mines of the Pamir Mountains were at their peak of productivity, countless high quality gemstones were unearthed and trafficked across Eurasia. Many of thes...

The Splendour of Spinel, part 3: Early Exploitation

Even though it is a lesser known gemstone, spinel’s history still stretches at least as far back as pre-Christian antiquity; some of the oldest known spinel gems were found in ancient buddhist tomb...

The Splendour of Spinel, part 2: Types and Treatments

Spinel is one of many gemstones for which there are numerous varieties. Just like its cousin corundum, spinel gems can occur in a myriad of different hues Very much like rubies and sapphires, spine...

The Splendour of Spinel, part 1: A Cousin to Corundum

Species Spinel Chemical Formula MgAl2O4 Mohs Hardness 7.5 - 8 Cleavage None Luster Vitreous to Subadamantine Refractive Index 1.719 - 1.920 Birefringence N...

Star Sapphire: A Stellar Corundum

  Species Corundum var. Star Sapphire Chemical Formula Al2O3 w/ TiO4, Fe2O3, and/or FeTiO3 Mohs Hardness 9 Cleavage None Luster Vitreous to Subadamantine,  w/ Silky an...

The Allure of Aquamarine, part 2 - Legends and Lore

Aquamarine has a long history as a revered gemstone. Blue and colourless beryls are thought to have been known to the Sumerians and Semitic peoples of antiquity, although definitive evidence of thi...

The Allure of Aquamarine, part 1 - Beautiful Blue Beryl

Species Beryl var. Aquamarine Chemical Formula Be3Al2Si6O18 with Fe2+ Mohs Hardness 7.5 - 8 Cleavage Indistinct Luster Vitreous Refractive Index 1.567 - 1.590 ...