Conference Call Transcript from
The Faceting Academy open conference call on Polishing
April 7, 2012
We’re talking about polishing, and we’re talking about the general ideas of polishing. And from the beginning, you know like I said, my friend, John Franke used to always say “polishing is Voodoo”, and that’s because it really is kind of mysterious in the way that things behave. And, part of what I want to do tonight is demystify some of that.
There is some question about “What is a polish?” And, “How polished is polished?” And, “How good a polish do you need?”
And, basically, what is a polish is – it’s a surface smooth enough that light either reflects off of it or passes through it, that light moves in a consistent way, and the flow of light isn’t broken; it’s not scattered, or deflected. Light moves in a smooth, unified pattern. And so, if that’s our definition of polish, then the question is: How smooth is that? How smooth does that need to be? And, in looking at that, you know my personal view is I look at the wavelengths of light.
Visible light falls between about four-tenths and six-and-a-half-tenths of a micron. So, if you’ve got a surface where the largest irregularities on that surface are under half a micron in size, then because that’s smaller than the wavelength of the light, you’re not going to visually perceive those disturbances, certainly not for the purposes of faceting and economic faceting. I’ll leave the competition where they’re putting everything under a microscope – somewhere in there they might see things that are smaller than that, but, for my purposes because I do not do that kind of faceting, I don’t care about that.
If the appraiser, with the tool he typically uses, the techniques he typically uses, if the appraiser cannot see it, then that’s what I’m shooting for. So we want the disturbances on the surface of the stone be well under a half of Micron size.