YIN/YANG crystals are half clear and half cloudy, that is half masculine and half feminine.   They embody both of these aspects and bring the polarities into balance; increasing here is depletion and reducing where there is excess.

DOUBLE TERMINATED crystals are whole crystals with complete, natural terminations (points) at both ends.  These crystals don't grow on a matrix like other crystals do; they form by crystallizing in soft muddy or sandy conditions.  Double terminated crystals are very useful healing tools because energy is able to flow both ways, due to their dualistic nature. They are great balancers of any body system, e.g. they can balance the left and right hemispheres of the brain and also yin and yang energies.
When placed between to chakra points they direct the energy to flow up and down the central energy line, when there has been a blockage or depletion of energy.  They may help unblock negative energy and are an excellent all round balancing tool.  Also, double terminated crystals may be used to promote psychic ability and dream recall (place under your pillow for this purpose) and they may aid communication.  One of the best known double
terminated crystals is from Herkimer County, New York, the so-called Herkimer Diamond (actually a silicate not a diamond at all).   It is a very powerful crystal and will amplify the energies of other crystals and empower essences.
 

GENERATOR (MERLIN) crystals are recognised by having 6 equal sides and 6 faces that meet together at a centrally located point, not as usual as might be thought.  They stimulate all levels of the body; physical, intellectual (mental), emotional, spiritual and subtle bodies (aura, chakras and meridians).   They have a general all purpose energy field useful in charging spaces with positive energy.  They may be used to bring wishes into reality, when used with the Intent for the highest good of all.
 

TABULAR or TABBY crystals are recognised by having two sides that are much wider than the other sides, making a wide, thin, flat crystal. These are used to enhance communication and creativity, to smooth energy flow, integrate ideas and bring balance.
 

RAINBOW crystals have prismatic fractures producing rainbows of colour within the crystal that can be seen when viewed in the right light. They brighten up life and bring an optimistic view.  They are beautiful to look at, as well!

WINDOW crystals have a diamond shaped face between two larger faces. They assist us in seeing within ourselves to our souls and in reaching the higher spiritual realms. They also help in assessing the energy levels of others.

TIME LINE crystals have a parallelogram alongside one of their faces on their point.  They allow your present self to communicate with your past or future selves; with the reality of existing in all dimensions and all forms at one time.  (Not for the faint hearted!).  They promote the concept of time as non-linear, with past, present and future all occurring in the NOW.   (For explanation of the NOW I can recommend Eckhart Tolle's book the Power of Now).  A right-sided Time Link (parallelogram turning in a clockwise direction) is said by some to assist in seeing futures, whilst a left-sided Time Link (parallelogram turning anti-clockwise) will assist viewing the past.  Personally I have not found this to be true.  Either way brings the same experience, as past is future and future is past and it is all in the present!!

TIME LINE crystals have a parallelogram alongside one of their faces on their point.  They allow your present self to communicate with your past or future selves; with the reality of existing in all dimensions and all forms at one time.  (Not for the faint hearted!).  They promote the concept of time as non-linear, with past, present and future all occurring in the NOW.   (For explanation of the NOW I can recommend Eckhart Tolle's book the Power of Now).  A right-sided Time Link (parallelogram turning in a clockwise direction) is said by some to assist in seeing futures, whilst a left-sided Time Link (parallelogram turning anti-clockwise) will assist viewing the past.  Personally I have not found this to be true.  Either way brings the same experience, as past is future and future is past and it is all in the present!!

RECORD-KEEPER crystals have small triangular shaped markings on one or more faces, which look as though they've been drawn, etched or carved in. They have been programmed by the beings that created the energies which have culminated life on this planet and may have been left by the Atlanteans and the Lemurians.  They are filled with wisdom and when you become properly connected with a record keeper crystal, the ancient knowledge and profound secrets of the universe can be uncovered.
 

SELF-HEALED crystals have healed themselves after becoming cracked or broken.  The damaged end is sealed over by new growth.  These crystals are considered powerful healers because of this action.  They bring confidence, motivation and optimism to those who feel damaged or broken on any level, i.e. physical, intellectual, emotional or spiritual.  This is due to their message of it is never too late, or too damaged to reach innate potential.

CHANNELING crystals have seven sides on their largest face and a small triangular face on the opposite side to this.  They are great for
meditation, where they are able to answer specific questions. When the large seven-sided face is held slightly away from the brow chakra (just above and between the eyes) or rubbed with the thumb, it can help to access and develop intuition.  This may be done to benefit those who read cards, runes etc.   It also helps provide a connection to the higher wisdom of the higher realms and higher self and may lead to communication with the Ascended Masters. This crystal facilitates a connection between our conscious mind and innate wisdom, as well as other planes of existence.

ISIS crystals are recognised by having at least one five-sided face,
usually at the front.  They help to balance yin/yang energies as well as
promoting the ability to view situations from a different perspective.
For men, they enhance the feminine side and help empathise with the female character.   For women, the isis helps regain some of the power and energy that society has taken from them.  Isis crystals symbolise human destiny, courage during adversity.  They help work through the fear of life and are excellent with issues of grief and dealing with loss.

PHANTOM crystals are recognised by what appears to be a smaller shadow or pale replica of the main crystal within itself.  These markings show where the crystal stopped growing, possibly for thousands of years, before continuing its growth.  These crystals are helpful for those whose own life was put on hold for a while, for example following a traumatic event, bereavement, severe disappointment, or other similar significant events, as they share an understanding and also demonstrate that life can and does, go on in a positive way.  Also they make good meditation tools focusing on creating deeper levels of awareness and memory recall.

BRIDGES are a large crystal with a smaller crystal(s) growing through or partly through the larger one.  It facilitates "bridging" between the inner and outer worlds and between the self and others.  It is a very useful aid when working with the different areas of spirituality and advanced metaphysical areas.
 

DOW crystals have three seven sided faces separated on each side by a triangular face, which is referred to as the 7-3-7-3-7-3 configuration. These are very potent numbers, as those of you who have studied numerology will know.  They can be used during divination to increase intuition as well as being a telepathic communicator.  They symbolise the ultimate inner truth, expression and communication and remind us of the circular trinity in constant motion (Birth, Death, and Rebirth).  It is THE crystal for creativity and service to humanity through both spiritual and mystical pursuits.  The Dow Crystal is named after one of the early channelers, Janeann Dow.

ELESTIAL crystals are recognised by multiple terminations, all facing in the same direction and appearing to have melted into each other.  Their unique look is created because unlike other crystals, elestials form in liquid.  They hold vibrations of the elements (fire, water, air, earth), as each of these are experienced by the crystal during their formation. This unique growth pattern enables elestial crystals to bring the body into a state of balance.  These are very powerful crystals and they will bring anything that needs to be addressed in your life to help your self-development, to your attention.  Be warned; work with these crystals ONLY if you are ready to make changes to your thought, behaviour or lifestyle patterns!  Elestial crystals are excellent aids for expanding consciousness, allowing communication with the higher realms and other dimensions, and facilitating astral travel.
 

SMOKEY QUARTZ crystals are associated with the base (root) chakra.  They are terrific at removing blockages to physical energy, particularly those that prevent us moving forward through fear.  They are great at dispersing negative energies of all sorts (place by a computer, microwave television etc) and are THE BEST at bringing grounding energies.

TWIN crystals are two similar sized crystals which have grown together and attached side by side. They promote tender communication and togetherness and assist in helping us find our soul-mate on a personal level.
 

GROUNDING crystals have an eight-sided main face.  It is an unusual crystal and helps to focus on the here and now, and lessens the need for denial, avoidance, blocking or fantasising.  It encourages the knowledge of the potential of current situation and in making things happen.
 

EXTRA-TERRESTRIAL crystals have a single termination at one end and multiple terminations at the other end.  It is believed this crystal will help channel space beings, celestial beings and guardian angels

LASER WAND crystals are long and slender with a pronounced tapering toward a very small point.  The crystal is wider at the base than at the tip and their sides are often slightly curved.  These are wonderful for concentrating a tight beam of energy on a small area.  They may then be used to stimulate an area hidden within the body, to *cut* through deep seated negative energy knots, for aura *sewing*, bringing energies into alignment, removing debris from the subtle bodies,  protecting the physical and subtle bodies, facilitating spiritual growth, to name a few of the uses of this powerful tool.  GREAT CARE MUST BE TAKEN WHEN WORKING
WITH A LASER CRYSTAL AND SHOULD ONLY BE USED BY THOSE WHO UNDERSTAND ITS POWER AND HOW TO WORK WITH THEM SAFELY.

KEY (Release) crystals are recognised by a three or six-sided shape
indented in the crystal that looks like a hole in the side of the crystal,
which becomes narrower as it goes within the crystal.  They are used to unlock blocks in the unconscious and to facilitate providing answers to deep questions about the self.

BARNACLES are formed when a larger crystal is covered with smaller crystals. The larger one is considered to be an "Old Soul" and has the wisdom and knowledge which attracts the smaller crystals.  It is often used for meditation where it facilitates insights to family and/or
community problems and the best way to resolve them.