Lighthouse lens cut

Hi, I have a question for the lapidaries on the list. A friend
brought me a sterling silver ring set with a 3ct synthetic ruby. The
stone was a lighthouse lens cut. Can anyone give me a little history
about this cut? I was also hoping to get an idea of the worth of a
stone like this. She was told the cut would make the stone worth
$70-100 retail. I’m a little skeptical about this number since it is
a synthetic stone so I was hoping for a more informed opinion.

Thanks,
Kristen
String Theory
Beautiful Beaded Jewelry
http://www.bcity.com/stringtheory

Hi Kristen, Just a note - Lighthouse Lens Cut is a registered
trademark of Strellman’s - we’ve carried the line for a few years, I
profess ignorance about the cut, my wife who is not here at the moment
knows it quite well. You may wish to contact Strellman’s through their
website http://www.strellmans.com/lenscut.html .

Russell
http://www.RussellsofCamden.com

Kristen, This may not be spelled correctly, but Fresnal lenses are the
lenses used in lighthouses. they are primarily used to focus a beam
of light from a source that was historically not too strong a light.
(oil burning lamps in the early days.) and direct this beam out to sea
for ships to see, and be warned of danger in that direction.

Recently I have seen some discussion of gem cuts using the same
principle as these lenses. I cannot for the life of me remember where
I saw the drawings of these cuts, but they seemed to be relatively
complex for gemcutting, and I would guess that I would not cut one for
less than the $70-$100 your friend was told about.

I know this is a bit sketchy , but perhaps will be a lead for you.

Bill Ehney
Facets of Newberry

There is a company called Strellman who trademarked the name “lens
cut” which is actually the fan cut from Vargas’ first book–you may
be talking about that facet patytern. Al Gilbertson

Kristen - your friend is right. The Lighthouse lens cut is a
proprietary cut belonging to Strellman’s - a company in Washington
state I beleive. It was inspired by the Fresnel lens used to amplify
the light emitted by a lighthouse - (tech workers in the theater see
another application of the Fresnel [pronounced Fruh’-nell] lens in
spotlights) Strellmens only does the cut in synthetics because it
wastes so much of the rough in the cutting process - thus the
relatively high price for a synthetic stone. When last I dealt with
Strellmans they would not sell the stones loose, only mounted in
their rings, pendants, etc. It is indeed an intriguing cut - fun to
work with and a challege to design a mounting for. Hope this info
answers your questions.

Mike