The Gemstone Iolite
Iolite is the gem variety of the mineral Cordierite
. It describes the transparent to translucent form of Cordierite, and it has recently become a popular gemstone. Iolite can be light to deep blue, and usually has a purplish tinge to it. Deeper colored stones are more valuable. Iolite is very affordable and durable, and can be used as a substitute for more expensive blue gemstones such as Sapphire
. It is named from the Greek "violet", alluding to the purplish tinge often exhibited by this gemstone.
Blue, Purple, Gray
7 - 7.5
1.55 - 1.62
Transparent to translucent
2.6 - 2.7
Iolite is strongly pleochroic
, and will exhibit a different color when viewed at different angles. In fact, it is the most pleochroic
gemstone, with this effect being clearly noticeable on all transparent Iolite gemstones. A blue or violet-blue Iolite gemstone will become a duller gray or grayish-yellow when viewed at a different angle. For this reason, care must be taken by gemstone cutters to facet Iolite gemstones so that their colors are oriented with the intense blue or violet showing from the top.
Iolite is cut into gemstone facets and cabochon
s, and is used in all types of jewelry, especially rings, earrings, and pendants.
Treatments & Enhancements
Iolite gemstones are natural and not treated or enhanced.
Iolite gem deposits are Madagascar, Myanmar (Burma), Sri Lanka (Ceylon), India, and Brazil.
- Lacks dichroism
, greater hardness
Iolite in the Rough Photos