Enhydros: Herkimer Diamonds with hydro inclusions are truly unique.  The value of an enhydro Herkimer Diamond is dependent on the size of the inclusion, size, and overall quality of the diamond, and movement of “floater” bubbles or “sinker” specks of anthraxolite inside the inclusion.  A nice hydro inclusion in good quality diamond can make the crystal worth as much as five times of what the diamond would be worth without the inclusion.

Solid Inclusions:  Many Herkimer Diamonds will have solid inclusions.  Black anthraxolite is the most common of solid inclusions found in the diamonds.  The presence of anthraxolite inside a diamond may enhance its beauty.  Other minerals which may be found as solid inclusions in the diamonds include iron pyrite, dolomite crystals, calcite, sphalerite, and garnet.  Value of a diamond with a solid inclusion is usually contingent on the aesthetics of the inclusion.

Twins & Doubles: Often, two diamonds which are attached to each other are found.  These sometimes result in very interesting configurations.  Occasionally, two attached diamonds that look very much alike are called “Siamese Twins”, or "Soulmates"...  Rarely, you may see what is called “Penetration Twins”...These are two Herkimer Diamonds which have grown together, with one partially or completly inside the other...It is not uncommon to find a diamond which has another smaller one attached.  These are sometimes called “piggy-backs”, or "Endo's"

Clusters: These are groups of Herkimer Diamonds which have grown together.  A cluster can make a spectacular display piece.  The majority of the time, a group of diamonds which formed together will break apart during the extraction process.  When the group appears to have a great deal of aesthetic potential, it can be well worth your time to reconstruct the cluster.  A high quality two part epoxy may be used to glue the group back together.  The Herkimer Diamonds can be brought back together by matching the attachment marks, like a Three Dimensional Puzzle,only there is only ONE Way they can be reassembled and there is No Picture to Guide you along the way... The value of a cluster is Dependent on its Aesthetics.  A nice cluster could be valued several times what the value of the diamonds alone would bring...

Tabulars: These are extremely rare.... A tabular will have two opposing center facets which have grown much larger that the other faces of the diamond.  This gives the crystal a flat tabular appearance.

Color Veils,Iris: Occasionally, healed fractures inside a diamond will refract a brilliant spectrum of rainbow colors when it is hit by light.  The diamond is worth even more if the healed fracture cannot be seen with the naked eye.  These may also be called “rainbows.”...The Ancient Romans called this Iris Quartz

Smokies: A Smoky Herkimer Diamond will have a very slight gray to black discoloration inside.  This discoloration sometimes will look like thin clouds of smoke settled inside the diamond.  This smoke is disseminated anthraxolite...

Skeletal or Elestial: A Skeletal or Elestial Crystal has depressed cavern in the center of one of the termination faces.  Skeletal have an interesting pattern of multiple fracture lines running parallel with two or more sides of a face on a diamond.  The lines appear to have occurred during the growth stage and are usually spaced in such a manner to give a three dimensional, holographic look when observed through on face.

Phantoms: A phantom crystal is one in which another crystal formed inside a larger crystal.  The phantom crystal trapped inside can often easily be seen with the naked eye.  These are very rare..

Matrix: Herkimer Diamonds in the Matrix can also be Valuable.  Unique Matrix Specimens may have Herkimer Diamonds on Matrix with Calcite, Drusy Quartz, or iron pyrite...Clusters in the Dolomite Matrix can also be Very Beautiful...

.,...........A Few Nice Ones................