Geology / History
Cordierite was discovered in 1813 & is named after the French geologist Louis Cordier. The transparent gem quality variety is known as Iolite. The name "Iolite" is derived from the Greek word for violet. Another old Greek name is dichroite meaning two coloured rock, named so because of its strong pleochroism. Gem quality Iolite varies in colour as the light angle changes from Sapphire blue to blue violet to yellowish grey to light blue.
It has also been called Vikings' Compass because the Vikings used it for determining the direction of the sun on overcast days. This works by determining the direction of polarization in the sky.
Light scattered by air molecules is polarized & the direction of the polarization is seen at right angles from a line to the sun. Iolite is also sometimes called Water Sapphire this term is due to its colour it is not a Sapphire. Bloodshot Iolite originates from Sri Lanka. It has a distinct reddish sheen or aventurescence, caused by Hematite & Goethite inclusions.
Cordierite - Iolite typically occurs in contact or regional metamorphism of argillaceous rocks & is common in hornfels produced by contact metamorphism of pelitic rocks. Cordierite also occurs in some granites, pegmatites & norites in gabbroic magmas.
One of the main industrial uses are in catalytic converters which are commonly made from ceramics containing large proportions of synthetic Cordierite. The manufacturing process Cordierite crystals are deliberately aligned to make use of the very low thermal expansion seen for one axis. This prevents cracking from thermal shock taking place.
Metaphysical Properties
The Goddess stone of abundance. Iolite releases a heavy heart bringing peace & love, shining light on unhappiness. It shifts negative into positive & is particularly good for maintaining a positive light vibration. Iolite shows us gratitude, this releases negativity & reenergises the mind, propelling one back onto their spiritual path.
As a stone of truth it helps you to see & speak the truth in a constructive manner, to bring about the highest good of all. Iolite teaches us to be in the moment & enjoy life, showing us how to be still with love to embrace our full potential. Through vision Iolite tilts time through past, present & future, showing us how we have been emotionally burned in the past then healing those emotional memories.
Wisdom & inner peace are received with Iolite, as it opens doorways into enlightenment it guides & supports us through each step. Iolite is excellent for all periods of transition & growth. It teaches when to rest or gestate ideas & when to actively create. Iolite brings balance, it cleans the debris from the auric field & activates all light centres. It overcomes exhaustion bringing fresh empowering motivation, helping us to keep sight of the bigger picture.
As a Shaman tool it has powerful fire & phoenix magic. Used through dream quests it is an excellent manifesting tool that protects & returns the soul home safely. In the physical realm Iolite protects the body’s aura from energy leaching & psychic attack, also dissolving attacking curses or spells. It brings trust in one’s inner fire & raises Kundalini energy into full circulating light.
Iolite will activate all chakra, however it connects strongly to the throat, third eye, crown & star chakra. Meditating with Iolite is an experience of your choosing it can be anything from blissful nothing to exploration of alternate realms. Iolite brings excitement, happiness & peace into the energetic & physical bodies.
Crystal Healing
Promotes detoxification, fat reduction, brain & nerve function. Assist with pain, stress, the eyes, migraines, headaches, memory, insomnia, nightmares or sleep disturbances. Improves degenerated conditions, digestion, follicle growth, circulation & immune system.
Mineralogy
Group: Silicate Mineral- Cordierite group
Crystal System: Orthorhombic, Dipyramidal
Composition: (Mg,Fe)2 Al4Si5O18
Form/Habit: Pseudo-hexagonal prismatic twins, as imbedded grains, and massive
Hardness: 7-7.5
Cleavage: Fair on {100}, poor on {001} and {010}
Fracture: Subconchoidal
Lustre: Greasy or vitreous
Streak: White
Specific Gravity:2.57 - 2.66
Transparency: Transparent, Translucent
R.I: nα = 1.527 - 1.560 nβ = 1.532 - 1.574 nγ = 1.538 - 1.578 Indices increase with Fe content.
Colour: Blue, smoky blue, bluish violet; greenish, yellowish brown, grey; colourless to very pale blue in thin section
Birefringence: 0.008 to 0.012
Fluorescence: None
Pleochroism: Strong trichroism: X = pale yellow, green; Y = violet, blue-violet; Z = pale blue
Strunz Classification: 09.CJ.10
Dana Classification: 61.02.01.01 Cordierite group
Causes of Colour: Violet to blue, Fe2+-O-Fe3+ charge transfer. Red, Hematite and/or Lepidocrocite inclusions