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The Private Reserve
Fancy Shape Desc.
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This is a perfect example of a feather that we would avoid. The feather is substantial, near the edge of the stone and runs the gamut of the stone through the girdle facet. A potential recipe for disaster, we rejected the diamond and returned it to the open market to be picked up by a less precise dealer. The first picture shows the feather from a side profile. The second photograph shows the feather from a top down view and the last picture shows the feather as seen from the pavilion (lower half) of the diamond.
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This series of photographs focuses on a feather which is located well within the body of the diamond and thus we feel it does not present any sort of durability risk. A feather such as this would not concern us in the least. The first picture shows the diamond as seen through our Gem Scope using a normal light source. We diffused the light source for the second picture to provide you with a different perspective of the inclusion. The third picture was taken using extreme magnification and at this level of magnification, the feather is a perfect example of why a feather is called a feather - notice how it looks just like a white feather off of a bird. We diffused the light source for the last picture.
Here is another example of a feather that we do not feel presents any sort of durability risk... This feather is larger than most, but is located well within the body of the diamond and does not exhibit any substantial stress points. The first picture shows the location of the feather within the diamond from a side profile. The second and third pictures are close-up's of the feather as seen through our Gem Scope at 30x magnification.
Natural: A "natural" is simply part of the original "skin" of the diamond that was left on the diamond instead of being removed during the cutting and polishing process. What is the "skin" of a diamond? Take a look at the picture of the uncut diamond rough at the top of this page and the rough exterior is what is considered to be the "skin" of the diamond. Essentially it is part of the original diamond rough which is the uncut crystal from which a polished diamond is crafted. Most often a natural is left on a diamond because removing it would reduce the weight of the finished diamond unnecessarily. Most naturals are located along the girdle edge of a diamond although we have also seen them on minor facets from time to time. We consider most naturals to be a perfectly acceptable type of inclusion, but give careful consideration to the location and extent of naturals during our selection process to determine whether they are acceptable to us or not. As recent as twenty years ago, it was quite common to find naturals on the "four corners" of a round brilliant ideal cut diamond (the North, South, East and West sections) because they served as proof to the owner of the diamond cutting factory that the cutter had not removed any more of the diamond rough than necessary.
This series of photographs focuses on a natural which is located along the girdle edge of the diamond in alignment with the triangular upper girdle facet, the natural is indicated by the red arrow. The first picture shows the inclusion as seen through our Gem Scope from a top down vantage point using a normal light source. We diffused the light source for the second picture. The last two pictures show the natural along the girdle edge as seen from a side profile using a normal and diffused light source.
This first picture is perhaps one of the best photographs of a natural that we have been able to capture, the crystal structure of the natural is actually visible. This natural has been polished so that it appears more crisp than most of the naturals that we see which are rough in appearance like the naturals pictured in the second and third pictures.
Indented Natural: an "indented natural" is simply a natural which is indented into the surface of the diamond... Indented naturals are often mistaken for chips by people who do not take the time to evaluate the inclusion under higher levels of magnification... Once again, the extent and location of the inclusion must be taken into account during the evaluation process to determine whether the inclusion is acceptable. The photographs above show a variety of indented naturals as seen through our Gem Scope at higher levels of magnification. Note that if an indented natural were actually a nick, pit, chip or cavity, that it would be described as such on the key to symbols as those are different types of clarity characteristics.
The girdle is the line which appears between the upper and lower halves of a diamond. There are several different ways to finish out the girdle edge of a diamond, the easiest is to leave the diamond "bruted" which is the result of the bruting process which shapes the initial shape of a diamond before it is faceted. Basically two round brilliant cut diamonds are placed in a machine so that the girdle edges of the diamonds will rub against each other as they are spun in a circle and the result is a kind of satin finished edge that looks like the first picture that appears above. Sometimes the cutter spends a little time polishing the bruted edge of a diamond so that it appears smooth and shiny and other times they add tiny facets to the girdle edge of a diamond as a finishing touch. Bruted, polished or faceted it really doesn't make a difference to us, the girdle edge of most diamonds is so small that it makes little difference. Personal preference, that's about it.
Bearding or "dig marks" are small feathers or breaks along the girdle edge of a diamond that are caused by the bruting process. We reject for substantial bearding.
Internal Graining: The comment on a lab report indicating "Internal Graining Not Shown" should not be reason for alarm because it refers to a clarity characteristic which is usually not readily visible without the use of extremely high magnification. Internal Graining should not be considered an "absolute characteristic" because the visibility depends on the lighting conditions and the specific angle by which the diamond is being evaluated. It might be visible to an experience diamond grader who is examining the diamond under laboratory conditions, but may never be detected by other people. Essentially internal graining refers to part of the grain structure of the diamond which was visible as a kind of transparent line to the grader. The degree of the visibility of the grain lines will have an effect upon the clarity grade of the diamond and if no other clarity characteristics are present then the graining may be the basis for the clarity grade of the diamond. For instance, a diamond that contained small diamond crystals which by themselves would warrant a clarity grade of VS-1 might be graded as a VS-2 if internal graining were present. However another diamond that did not contain the diamond crystals might be graded as VVS-2 if the grade is based upon internal graining and the comment "clarity grade based upon internal graining" would appear under the "comments" section of the lab report while nothing is indicated under the "keys to symbols" by the plotting diagram.
This series of photographs shows the very subtle effect of
internal graining as seen within a diamond we purchased for inventory at
various degrees of magnification. Notice how the internal graining
is not readily visible in the first picture which was taken using a
magnification level of about 20x. The internal graining is barely
visible in the next two photographs which were taken of the table facet
at about 40x magnification, the grain line appears as a kind of
translucent line as indicated by the light blue arrows. We
increased the magnification substantially for the remaining pictures
which show the internal grain line as seen through our Gem Scope using
normal and diffused light sources.
Surface Graining: The comment on the lab report referring to "Surface
Graining Not Shown" sounds kind of serious but it really isn't...
Surface graining is essentially a transparent line that is part of the
grain of the diamond which happens to be visible across a facet
junction. It is essentially the same thing as Internal Graining
but it resides on the surface of the diamond instead of being within the
crystal structure of the stone. If the surface grain line were
within the structure of the facet and not crossing over the facet line
it wouldn't be mentioned on the lab report because it would be
considered a characteristic of polish. Most surface graining is so
insignificant that we are rarely able to find it and when we do it is
because we are using extensive magnification like 50 - 70x which is
substantially higher than the industry standard of 10x which is supposed
to be used for diamond grading. In the case of a diamond graded as
Internally Flawless in clarity, as a general rule it is likely that the
diamond may have been graded as Flawless instead of Internally Flawless
if the surface graining were not present.
The facets of a diamond are essentially tiny mirrors which serve to reflect light back up towards the surface of the diamond. Quite often these mirrors will also cause an inclusion to reflect within the diamond so that it appears more numerous than it really is and so that it appears to exist in areas of the diamond where it was not. This phenomena can make it quite challenging to correctly identify the inclusions within a diamond, represent the position of inclusions accurately and sometimes to even locate a specific inclusion based on the plotting diagram provided on the lab report. The first picture provided above is a perfect example of the dilemma we are describing, click on the thumbnail to view the full size picture and try to figure out which of the white specks is the real diamond crystal. The second picture is an excellent example of how inclusions located on one side of a diamond as indicated by the red arrows can reflect to another location within the diamond as indicated by the light blue arrows. Reflections within a diamond are essentially a product of the design and facet structure of a diamond and are to be expected, the trick is trying to determine what is real and what is illusion.
The term Twinning Wisps, also known as Intergrowth, is used to describe the formation of inclusions which have twisted together within a twinning plane. The formation might include a variety of inclusions such as pinpoint size diamond crystals, fractures, crystals, feathers and clouds. The formation often looks like white striping within the diamond similar to stretch marks on skin. Twinning wisps are most often found in fancy shape diamonds such as pear shapes, heart shapes and triangles because they are often fashioned from twinned crystals, however twinning wisps can appear within other diamond shapes as well depending on the quality of the diamond rough that was used to make the stone. We seldom see twinning wisps within the ideal cut diamonds that we sift through for our inventory because most of the cutters that we work with produce higher end goods and thus would remove the intergrowth from their production, however we have seen twinning wisps in lower quality goods which are produced by companies who's primary focus is larger, inexpensive diamonds in which case they work with less expensive, lower quality diamond rough to shape their production.
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