I thought I would set a little challenge today...   One is lapis lazuli, one is ‘synthetic’ lapis lazuli and the other is sodalite - do you know which is which? A tough challenge from a photo I know (and you shouldn't really ID a stone from a photo, but this is just for fun and to show you them side-by-side)…

The smaller stone on the bottom right is natural lapis lazuli. Comprising of lazulite, calcite and pyrite; colour may be patchy with blue lazulite and white calcite and any pyrite grains will have an irregular appearance while being distributed unevenly through the stone.

The largest stone at the top is ‘synthetic’ lapis lazuli – this is a sintered powdered material that doesn’t have any of the physical, optical and chemical properties of natural lapis lazuli. Any sparkling pyrite grains present tend to be small with regular edges and scattered evenly throughout the stone.

The smaller stone on the bottom left is sodalite and whilst it may have some white veining it has a darker colouring compared to the brighter blue of lapis lazuli and does not contain pyrite grains.

There are a number of other stones which can imitate lapis lazuli including dyed howlite, dyed magnesite and ‘Swiss lapis’ which is a dyed jasper.  Always good to do some reasearch when buying stones and know what is on the market!