How to Identify Genuine Lapis Lazuli: Expert Tips to Spot the Real Stone
Lapis lazuli, with its striking deep blue hue and golden flecks, has captivated humanity for millennia. From adorning ancient Egyptian jewellery to being ground into the precious ultramarine pigment of Renaissance art, this gemstone's allure is undeniable. However, the market today is rife with imitations, making it essential for enthusiasts and buyers to discern the genuine from the fake. This guide will walk you through the key characteristics of authentic lapis lazuli and offer practical tips to ensure you're investing in the real deal.
In short: Genuine lapis lazuli (Mohs 5-5.5) shows deep ultramarine blue with pyrite (golden flecks, not silver) and calcite (white veining). Imitations include sodalite (no pyrite, more uniform colour) and dyed howlite (colour rubs off with acetone). Test with a streak plate: genuine lapis leaves a blue streak; specific gravity 2.7-2.9.
Understanding Lapis Lazuli
Lapis lazuli isn't a single mineral but a composite rock primarily composed of lazurite, which imparts its signature blue colour. Other constituents often include calcite (white streaks) and pyrite (golden flecks). Historically, the most renowned deposits are found in Afghanistan's Badakhshan province, with other sources in Chile and Russia.
The Prevalence of Imitations
The high value and demand for lapis lazuli have led to a surge in counterfeit versions. Common substitutes include dyed howlite, sodalite, and even glass. These imitations can be convincing, especially to the untrained eye, making knowledge crucial for accurate identification.
Distinctive Features of Genuine Lapis Lazuli
Colour Variations
Authentic lapis lazuli showcases a rich, deep blue, sometimes with slight variations towards violet or greenish-blue. Uniformly bright or overly vivid blue stones may indicate dyeing or synthetic origins.