How important are proper pavilion angles in a nice deep green
emerald? Which way of cutting will preserve the most value?
Hans, I'll give you the benefit of my vast, er, opinion... ;o)
Emeralds are valued more for color and size than light reflection
and brilliance. Of course it's best if you can "have it all." If the
rough has rich saturated green color I'd recommend going for the
biggest possible stone. Beryl's relatively low refractive index
combined with typical low clarity due to the infamous "jardin"
usually preclude high optical performance anyhow.
On the downside, if the stone is relatively clean with good
transparency, cutting the pavilion below the critical angle will
obviously result in a window you'll be able to see the mounting
though. If you're cutting the typical emerald cut you might consider
adding more than the usual number of pavilion facets to get a little
more light breakup. Just my two cents; it's impossible to judge
without seeing the stone.
Rick Martin MARTIN DESIGNS