How To Correct Faceting Mistakes

We faceters all like to take pride in our work. However, no matter our skill level, we all make errors. However, you can learn a few tricks for correcting faceting mistakes. These will save you considerable effort. Furthermore, they might even lead to new designs and a better understanding of gem optics.

Missed Index

One of the most common faceting mistakes we make is not setting the index correctly on our faceting machines. If you miss it by just one notch, it’s enough to throw off the entire design.

Here’s the diagram for a meetpoint oval being cut with a 64 index gear. You should cut the shaded facet at 44.7° and I 7, (followed by I 25, 39, and 57.)

Now, say you make a mistake and cut it at I 8. If so, you should cut symmetrical facets all the way around, using indexes 24, 40, and 56.

How do you determine that?

The Solution

Simply add and subtract the proper number from your top and bottom index settings. This index gear has a setting of 64 (or 0) at the top and 32 at the bottom. We started with 8 from the top. Therefore, subtract…