Right, however the original question posted asked "what is a knot on a GIA diagram" thus the explanation is based on the definition of a knot as defined by the GIA... We're not at the obvious and don't have the lab report in front of us, but seem to recall that it was an SI-1 or VS-2 graded stone...----------------
On 3/19/2003 10:59:20 PM dimonbob wrote:
GIA is not the last word nor the only authority when it comes to all things Gemology.
Robert Webster & Peter Read both from the British counterpart to GIA have written several books on the subjects of diamonds and gemology.
A quote from Gems: "Twinning may also occur locally within the crystal (diamond) producing "hard" spots which are frequently called "naats" or "knots".
I do not disagree that a surface reaching included crystal may also be a knot but the point is that the knot is oriented in a different direction than the facet that it is on and would be a hard spot and very difficult to polish. Twinning whisps are something entirely different.
That is a fairly large knot in that picture. I am interested to know what GIA clarity graded that stone?