what is the difference between iolite and tanzanite both are semi precious stones?

Iolite is a mineral sometimes used as a gemstone. Gem quality a sapphire blue in color to a bluish violet color to yellow gray in color depending on refraction of light It is found in Burma and Sri Lanka. Actually called, cordierite. On the Mohs hardness scale about 7 to 7.5

The two stones can be confused but are very different and especially when price comes into the conversation as tanzanite is a rare stone that is very very pricey.

Tanzanite is a marketing name by Tiffany & Co. and this stone is not popular with alot of people because of the mining industry of Tanzania. They make a great deal of money off this stone while using methods many people find deplorable. It is still. It is a purple stone generallly after heat treating because it comes out of the ground a bronze color. It has a Mohs hardnes of 6.5 to 7

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