Gem: Chrome Kornerupine
Weight: 1.49 ct.
Dimensions: 7.4 mm round x 2.95 mm tall
Clarity: SI
Origin: Umba Valley, Tanzania
Treatments: None
Comments:
I took this intensely purple chrome kornerupine cabochon that I had, and re-cut it to exclude a nasty fracture that went clean across the top of it. More or less I gave this bad boy a deep haircut, and glow up. The gem is still quite purple on its C axis (seen looking through the crown / table). Looking sideways through the gem, you see the A-B axis color: a glowing, vibrant teal color!
I faceted this rose-cut gem to preserve BOTH colors to the viewer at the SAME time! The steep angles on the side are 80, 70, and 59.5 degrees, while the crown angles are 20, 16, 9, and 0 degrees. The large gap in between those sets means green colors stay green to your eye, and purple colors stay purple to your eye, because all of the angles that would cause mixing are omitted! While an 'in between' set of facets would produce a blue color in this gem, and make for a nice taper between purple, and green, but it would also steal depth of color from the purple axis, which is something I didn't want. I wanted the MOST purple I could get.
The result is a phenomenal success, I don't mind saying. The gem's pattern is visually striking, it's dichroism is visually striking, and itis a great size fora low-profile ring.