The Pentafan Gemstone Design
The Pentafan is a unique cut designed for larger gems with deep color saturation. Learn how to cut this design that can make dark stones shine.
1 Minute Read
Flashes from a Dark Gemstone
Even though the color saturation was quite deep, it turned out to be a great performer. There are continuous flashes of color as the gem is moved.
There is also a uniform dispersion of light throughout the stone, instead of the standard bright center surrounded by dark regions.
Pentafan Cutting Instructions
|1||40º||120-024-048-072-096||Cut to PCP|
|3||41.5º||004-020-028-044-052-068-076-092-100-116||Meet P1, P2 @ Corner|
|4||43.5º||006-018-030-042-054-066-078-090-102-114||Meet P1, P2, P3 @ Corner|
|5||46.9º||008-016-032-040-056-064-080-088-104-112||Meet P1, P2, P3, P4 @ Corner|
|6||61º||012-036-060-084-108||Meet Others @ Corners|
|1||19º||120-024-048-072-096||Set Girdle Thickness|
|3||12º||006-012-018-030-036-042-054-060-066-078-084-090-102-108-114||Meet C1, C2, C1 form TCP|
|4||0||Table||Meet C3, C1, C3|
A note from Donald Clark: D. R. Jerkins apologized that he couldn't send us an example of the Pentafan gem design sooner. As it turned out, the gems sold out too quickly. Now that's a problem we should all have!
D. R. Jerkins
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