Yin & Yang Double Terminated
Yin & Yang DT 
Clarity - The first impression of quality or value of natural crystal is usually judged by the clarity.  The clarity ranges from milky white to glass clear that sparkles like a cut diamond.  Most crystal is milky white at the base and gradually clears to the tip.  The milky white crystal is said to represent the yin or feminine qualities of love, communication, negotiation and receptivity.  The clear crystal represents the yang or masculine qualities of power, force, strength and creativity.  A crystal with both is believed to promote a balance of the masculine and feminine energy on both physical and mental levels.  Large, water-clear crystal points with smooth sides are quite rare and consequently, more valuable.  I guess a good man is hard to find. This double terminated crystal has both yin and yang.
Double Terminated
Double Terminated Crystal
Double Terminated - A crystal with a point at each end is called double terminated.  It is believed that they have the ability to receive or transmit energy from both ends.  They are used for alignment, patience, perseverance, protection, dreaming and astral projection. . Double terminated crystals strengthen energy flow, and are especially useful when you need to share or exchange energy between you and another person. Double terminated crystals are very important to people doing healing work for themselves or others. 
Generator
Generator Crystal
Generator (also know as a Merlin Crystal) - A crystal with six evenly spaced sides and six approximately equal faces that center at the tip is called a generator point.  It is believed that they have the ability to store, amplify and transmit or generate energy.  They are used to facilitate a connection or create unity between the members of a group and transmit thoughts in a manner similar to a high power radio transmitter and antenna. 

Tabby Crystal
Tabular Crystal - A crystal with a flattened tabular shape and two of its opposite sides are twice as wide, or more, than its other sides, giving the appearance of a tablet is called a Tabby crystal.  It is believed they can help us access information and are considered the ultimate communications crystal.  They are a bridge between our adult self and our child like spirit.  They can help us lighten up and laugh a lot. 
Crystal with a Faden line
Faden-Lined Crystal 
Faden-Lined Crystal - are crystals that have clearly visible within their interior structure a milky feather line, that usually runs through the crystal.  Faden lines manifest primarily in tabby shaped crystals, but have on extremely rare occasions, have been found in a normal single point crystal.   It is believed that the line represents the seed point of growth and they have the ability to activate or start new growth within one's self or within someone you are working with, utilizing healing energy.
Rainbow
Rainbow Crystal
Rainbow Crystal - A crystal with a rainbow(s) inside that is caused by light being refracted by the prismatic effect of a crack or inclusion is called a Rainbow.  The refraction is often temperature sensitive causing the rainbow to appear and disappear.  It is believed that these crystals exhibit the closest manifestation of pure white light that can be witnessed on the physical plane. Rainbow crystals are used during meditation to escort us into the realm of the pure white light and can bring depth and clarity to dreams, help manifest wishes, and overcome negativity to be able to love life in the present moment.
Window
Window Crystal
Window Crystal - A crystal with a diamond or rectangular face between the body and tip of a point is called window.  It is believed this crystal will open a ‘window to your soul.’ and help you get intuitive answers to questions and bypass the ego or intellect.  They are used for clarity and direction. If you are having problems and aren't sure why, a window crystal can be a good help. 
Time Line to the Past
Time Line - Past (left)
Time Line to the Past - A crystal with a rectangular face leaning to the left.  It is believed they can be used to access information from the past.
Time Line to the Future
Time Line - Future (right)
Time Line to the Future - A crystal with a rectangular face leaning to the right.  It is believed the can be used to access information from the future.
Record Keeper
Record Keeper
Record Keeper - A crystal that has pyramidal or triangular shaped symbols that are either engraved into or are raised on one or more of a crystal faces is called a Record Keeper or Recorder.  These symbols are not easily seen and usually need to be searched out by looking at the crystal in a bright light while closely examining the faces. It is believed that the Record Keeper is one of the most sacred crystals because it holds the wisdom and knowledge of the universe.  When a person is properly attuned to a Record Keeper, this knowledge is readily made available. This knowledge is ancient knowledge and contains profound secrets and esoteric knowledge of the whole of the Higher consciousness.  It takes an open mind and a pure heart to access this knowledge. 

Self-Healed Crystal
Self-Healed and/or Shard Crystals - A partial piece of crystal or a complete crystal that has severed from its original matrix or cluster group, then at some later time the conditions were correct  to continue to grow new crystal structure over the area where the crystal separated from its original host, in effect healing its own wounds. It is believed that this crystal will aid in any type of self-healing—physical, emotional, mental, or spiritual. Self-Healed crystals are exceptionally supportive for those with strong emotional issues or traumas, or are struggling with some type of addiction that includes the inability to let go of certain kinds of behavior, a person, or belief, as well as tobacco, food, alcohol and drugs.
Channeling Crystal
Channeling Crystal
Channeling Crystal - A crystal with a large seven-sided face with a triangular face on the back side is called a channeling crystal.  It is believed the Channeling crystal can be used for obtaining information from deep within yourself or from sources that are outside of your normal realm. The number seven is a metaphysical number symbolic of the student, the mystic, and the seeker of deeper truths and spiritual wisdom. Each side of the seven sides of the main face represents the  seven qualities that the human consciousness must attain in order to access and channel the wisdom of the inner soul. 
Isis Crystal
Isis Crystal 
Isis Crystal - A crystal with a five-sided face is called an Isis crystal.  It is believed the Isis crystal will put you in touch with and strongly amplify your feminine energy, and can help you get in touch with the 'female' or unselfish side of yourself, no matter whether you are a man or a woman. Isis crystals put you in touch with the power of the Goddess. For men, the Isis crystal will help you become more in tune with your feminine side and to become more aware of the aspects of women that you may find troubling. For women, the Isis crystal will help you regain some of the power and energy that society has taken from you. 
Inclusion in crystal
Included Crystal
Phantom & Included Crystal - A crystal with another mineral or substance included within. Some have layered points resembling pyramids of crystals (phantoms) and some may just have specks or globs of included material.  The more common inclusions are black, green, brown and white. 
Bridge Crystal
Bridge Crystal
Bridge Crystal, Inner Child Crystal or Penetrator - A crystal that has a smaller crystal(s) that either penetrates and/or is lodged partially into the crystal with the other part protruding from the crystal is called a Bridge crystal.  It is believed this crystal is quite beneficial when a person is striving to work with various aspects of spirituality or to heal childhood issues blocking growth.  Additionally, these crystals are their best when the person is working on advanced metaphysical areas, and are attempting to share this knowledge with others seeking a spiritual path.  This is the ultimate spiritual teacher's crystal.  This unique example has a double terminated point running clear through the larger point. 
Manifestation Crystal
Manifestation Crystal 
 Manifestation Crystal - A crystal with a small crystal totally enclosed within is called a Manifestation crystal. It is believed to help people who have had a traumatic, physically or emotionally childhood. They are helpful for people who are blocking painful memories. They help bring the cause of the pain to the surface and allow the person to successfully deal with it, while shielding that person from the pain those memories can cause. These crystals work well for people who are working through current family problems. 
Dow
Dow Crystal
Dow or Trans-Channeling Crystal- A crystal with three, primary, seven-sided faces and three secondary triangular faces between them.  It is believed this crystal is a combination crystal that incorporates the properties of both a Channneler and a Transmitter crystal in one crystal. It helps facilitate intuitive awareness and connection with “All That Is”.  It is considered one of the "Twelve Master Crystals" and is a powerful teaching and healing crystal.

Elestial Crystal
Elestial Crystal -  A crystal with natural terminations over the body and faces, resembling the human brain, is called and Elestial Crystal.  Most bear a smoky color.  It is believed this crystal can repair damaged cells in the brain and rewire the damaged areas to bring back new life. They are powerful, powerful crystals that have been brought into this reality, at this time, to assist in the mass cleansing, healing, and reawakening that is currently occurring on this reality plane.  Elestials are the great comforters to those who are in the dying process and they assist to release the fear of leaving the physical body in order to identify with the immortality of the soul. 
Natural Smoky Crystal
Natural Smoky Crystal
Natural Smoky Crystal - A crystal with a golden brown to black translucent color caused by natural earth radiation is called a smoky crystal.  This is a small golden smoky cluster with two points.  Each point has a time line to the future. 

Twin Crystal
Twin Crystal or Tantric Twin - A crystal with two points on a common base is called a twin crystal.  You can tell a twin crystal from two crystals that are simply attached to each other, by the fact that both parts of a twin crystal are exactly parallel to each other, and have no boundary between them. It is believed the Twin crystal can generate positive energy toward improving a relationship.  They can help you gain insight into the underlying problems in a relationship, and help work through them.  This works for any kind of relationship, not only a man-woman relationship. A twin with a rainbow can be very effectively used to project healing energy into a relationship or to keep a good relationship strong. 
Grounding Crystal
Grounding Crystal
Grounding Crystal - A crystal with an eight sided face is called a Grounding crystal. They are quite rare. It is believed that this crystal will help you deal with practical matters in a realistic way. They will help you think and express yourself clearly when dealing with issues of every day life.

Extra-Terrestrial Crystal
Extra-Terrestrial Crystal (ET) - A crystal with 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.
Japanese Law Twin - These crystals have a twin points at a 90 degree angle.  Very rare! This one is in a cluster with the tip or the horizontal point hidden behind the vertical point on the right. 
Laser Wand Crystal – A long slender crystal that tapers inversely from base to termination is called a laser wand.  It is believed the laser wand can be used to clear negativity, create protective barriers, focus healing energy to self or others, and assist in performing psychic surgery to remove attitudes that may be causing disease.
Key Crystal – The key crystal is recognized by a three or six-sided indentation somewhere on the crystal. It is believed the Key crystal can be used to unlock the doors to healing, help answer difficult questions, solve problems, and access information to that which is hidden.
Growth Interference Crystal - A crystal that has various cuts on the body that appears to have been done with a trim saw.  Thin, flat calcite crystals have interfered with the growth pattern of the quartz crystal. It is believed this crystal will help remove self-limitations and energy blockages so that you can be completely in command of your life.
Barnacle Crystal - A crystal covered or partially covered with smaller crystals.  It is believed the Barnacle crystal will help stimulate family or group cooperation.  Also a companion when having lost a loved one.