Geology / History

Opal is a hydrated amorphous form of silica its water content may range from 3% to 21% by weight, but is usually between 6% & 10%. Because of its amorphous character it is classed as a mineraloid, unlike the other crystalline forms of silica which are classed as minerals. It is deposited at a relatively low temperature & may occur in the fissures of almost any kind of rock.

Opal is most commonly found with limonite, sandstone, rhyolite, marl & basalt. Opal is the national gemstone of Australia, which produces 97% of the world's supply. South Australia accounts for approximately 80% of the world's supply.

The internal structure of precious opal makes it diffract light & show a variable interplay of internal colours depending on the conditions in which it formed, it can take on many colours. Even though it is a mineraloid, it has an internal structure.

At micro scales precious opal is composed of silica spheres some 150 to 300 nm in diameter in a hexagonal or cubic close-packedlattice. These ordered silica spheres produce the internal colours by causing the interference & diffraction of light passing through the microstructure of the opal. It is the regularity of the sizes & the packing of the spheres that determines the quality of precious opal.

Precious opal ranges from clear through white, gray, red, orange, yellow, green, blue, magenta, rose, pink, slate, olive, brown, & black. Of these hues, the reds against black are the rarest, whereas white & greens are the most common. It varies in optical density from opaque to semi-transparent.

Common opal is called potch by miners & does not show the display of colour exhibited in precious opal.

Metaphysical Properties

All opals are fierce protectors of light, keeping their human friends surrounded in a forcefield of radiant light. They increase emotional strength & open the mind to its higher self. Opals are stones of great magic & good fortune making them fantastic for manifestation of all kinds. A powerful ascension stone which teaches us how to embrace our light to remove darkness, create joy & understand oneness.

Opals deflect negative energy & returns it to the source. They teach us about connectivity, this removes the illusions seen within human life & brings forth the truth in our own divinity. Opals are very powerful & will release negative emotions & trigger point from traumatic experiences.

Much like Obsidian, Opals show us our darkness giving us the courage to understand, embrace & integrate it into the whole divine being, stopping us from seeing darkness as a barrier to light. They hold ancient wisdom & secrets to enlightenment.    

White Opal: A very fine & delicate energy. Aids in expressing your true self. A protective stone especially when venturing into dangerous places. Brings loyalty & spontaneity. Reflects negative energy back to its source.

Blue/Green Opal: Opens to new impressions & encourages openness. Helps to see the world with new eyes. Alleviates emotional burdens & liberates feelings.

Green Spots Opal: Promotes emotional recovery. Helps to balance relationships. Gives meaning to everyday life. Cleanses & rejuvenates. Alleviates colds & flu.

Pink Opal: Activates clairvoyance. Helps to heal headaches that arise from a blocked or unopened third eye. Promotes tissue regeneration, heals blood disorders, muscle tension & spinal disorders. 

Crystal Healing

White Opal: Strengthens the will to live.  Aids Parkinson’s disease, fevers, purifies blood, regulates insulin, eases childbirth.

Blue/Green Opal: Detoxifies & regenerates the liver and relieves feelings of tightening of the heart & chest.

Mineralogy

Group: Mineraloid

Crystal System: Amorphous

Composition: SiO2·nH2O

Form/Habit: Irregular veins, in masses & nodules

Hardness: 5-6

Cleavage: None

Fracture: Conchoidal, uneven

Lustre: Subvitreous to waxy

Streak: White

Specific Gravity: 2.15

Transparency: opaque, translucent, transparent

R.I: 1.450

Colour: Colorless, white, yellow, red, orange, green, brown, black, blue, pink, purple

Birefringence: None

Pleochroism: None

Fluorescence: black or white body colour: inert to white to moderate light blue, green, or yellow in long and short wave. May also phosphoresce; common opal: inert to strong green or yellowish green in long and short wave, may phosphoresce; fire opal: inert to moderate greenish brown in long and short wave, may phosphoresce

Wearing Opals - With doublets & triplets it is best to not expose them to water. Do not expose Opals to any chemicals.