How can you tell a fake iolite?

Despite its affordability, you may still come across Iolite 'fakes'. These will generally be colored glass, so simply look for depth of color, proper reflection of light, and hardness of the gem to identify the fake stone. Glass is much softer than Iolite, and may already be scratched – a dead give-away!

Is iolite blue or purple?

Typically, iolite ranges in colour from light to dark blue, and even violet. However, the stone is also known to occur in different hues including green, brown, yellow and grey. The most desirable shade of iolite crystal is a very intense violet blue that rivals that of tanzanite.