lion main facet as
you would see it through a flat-top gem (100% table), without
distortion by refraction. However, this perfect view is
disrupted when the table ends (heavy red line); beyond which
this outline appears, distorted by refraction, in the crown main
facet just above it.
Because the pavilion main facet slope is 45�, this outline is
also that of the far pavilion main being reflected in the near
one!
WITH A Newsletter-06/' >PRACTICAL PAVILION SLOPE
In Fig.2 we have the ideal pavilion main slope of 40.75�.
Again the direct view of the pavilion main is outlined in black
and is undistorted until it reaches the edge of the table (heavy
red line). The remainder appears distorted by refraction in the
crown main facet just above it (this is the tip of the arrow).
The reflection of the opposite pavilion main, in the near one,
is shown in green. Both ends of it disappear the culet end
because of the limits of the near pavilion main, and the girdle
end because of the table edge.
The thin blue lines show the reflected outlines of the far
crown main and stars as they would appear on the plane of the
near pavilion main (via the far one) if it was large enough, and
seen through the table if it was wide enough.
The area within all of these limits is the shaft of the arrow,
which is black by certain viewing.
The culet does not show in the Newsletter-06/' target='blank' class='doin' >bezel a criterion the author
once used to define minimum table size, based on 2D-analysis.

3 REFLECTIONS
Fig.3 shows the same stone considering the first 3
reflections. The arrow, familiar in diamond, is outlined in
black. The black hole (red arrow) now has four parts;
Newsletter 07 isolates the sources of this on the sphere.
. Now the culet appears in the Newsletter-06/' target='blank' class='doin' >bezel (blue arrow) but it is
very faint in realistic images.

INTENSITY vs. EDGES
Intensity is not considered in showing edge reflections; the
real image of the culet is barely noticeable because of its low
intensity. Fig.4 shows that 2 reflections of the light source
reach the viewers eye at 63% of source intensity, while 3
reflections show only 13% of whatever comes from the culet
(which is only 15% of what originally entered the crown)

BLH 2004 Jul 28