Corundum

The mineral whose chemical formula is Al₂O₃ is known as corundum.

Corundum exists in many colours but is best known as the precious stones sapphire (blue corundum) and ruby (red corundum). These are most commonly used in jewellery and so may be most easily recognised when polished.

Corundum crystals in all their forms have metaphysical associations, see below.
In some cases it is preferable to use natural rather than polished forms of corundum.

Structures of corundum crystals

Corundum consists of the chemical elements aluminium and oxygen arranged in the trigonal system of crystal symmetry. This system of crystal symmetry includes four axes, three of which are of equal length and arranged in the same plane, the fourth axis being perpendicular to this plane and of different length from the other three.

Corundum crystals are usually found in the form of either rough, barrel-shaped prismatic forms (as shown above), or tapering, spindle-shaped forms.

Distinguishing features of corundum

This is how to tell if a crystal is corundum rather than another similar material.

All of the following apply to corundum:

• Hardness of 9 (the second hardest mineral)
• Specific Gravity of 3.9 - 4.1
• Distinctive crystal form - see photographs on this page

Associations of Corundum

Corundum has various metaphysical associations, including:

• Facilitating insights into the unknown
• May enhance intuitive awareness
• Stimulates ambition and confidence
• Subdues negative emotions
• May facilitate positive release of frustration and anger

There are also other metaphysical associations with particular colours of corundum crystals - summarised below.

Colours of Corundum Crystals

The two main varieties of corundum crystals are blue (sapphire) and red (ruby). Other colours of corundum crystals include: black, bronze, green, grey/brown, indigo, orange, pink, purple, white and yellow.

Additional metaphysical associations with the colours of corundum crystals include:

Ruby Corundum Crystals Choice and attainment of values Protection, in disputes and against psychic attack Stability of economic circumstances Maintaining connections, such as with other people or with places Assisting with access to the ancient teachings of India ("Merlin's Crystal Mine" in India is a source of ruby) Astral Travel	Sapphire Corundum Crystals Freedom from unwanted thoughts Lightness and joy
	Blue - Communication, Astral Travel Black - Protection and grounding, seeking or maintaining employment Green - Loyalty, fidelity, remembering dreams Indigo - Alertness, attentiveness, encouragement, ambition Purple - Spirituality; Meditation White - Focus; Directing Attention Yellow - Wealth, Stimulation of the intellect

Ruby (Red) Corundum Crystals:

• Choice and attainment of values
• Protection, in disputes and against psychic attack
• Stability of economic circumstances
• Maintaining connections, such as with other people or with places
• Assisting with access to the ancient teachings of India ("Merlin's Crystal Mine" in India is a source of ruby)
• Astral Travel

Sapphire Corundum Crystals:

• Freedom from unwanted thoughts
• Lightness and joy
• Communication
• Astral Travel

Associations of other colours of Corundum Crystals:

Black	Protection and grounding Seeking or maintaining employment
Green	Loyalty Fidelity Remembering dreams
Indigo	Alertness Attentiveness Encouragement Ambition
Purple	Spirituality Meditation
White	Focus Directing attention
Yellow	Wealth Stimulation of the intellect

The photograph on the right is of a blue (sapphire) corundum crystal. This example is translucent and natural, i.e. unpolished.