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The Rings Book by Jinks McGrath


#1

I found the book, “The Rings Book”, by Jinks McGrath, at the local
library.

(So impressed I have ordered a copy of my own!) But there’s one thing
I’m not understanding; hopefully the forum can explain…those of
you who have the book, that is…

On page 69 a description is given of how to draw templates for
making a mount for faceted stone. Nearby there is a drawing that
shows the term “culet” refers to the bottom of the stone, where it
comes to a point or a single line. At the top of the right-hand
column the text indicates that the culet should have a measurement
(of its own). How can that be? If it comes to a point or a line, how
can it have a diameter?

This culet measurement is distinct from the vertical distance from
girdle to culet. Does the writer mean the linear distance along the
outside of the stone from bottom of girdle to bottom or stone? Or am
I missing something here?

When looking at the diagram on at the bottom of the page, it shows a
circular dimension for the culet, not a point.

Many, many thanks for all responses. I’m on the verge of setting all
my faceted stones (finally!!).

best regards,
Kelley


#2
that the culet should have a measurement (of its own). How can
that be? If it comes to a point or a line, how can it have a
diameter? 

Hello again, Kelley. The culet of a stone is considered a facet.
It’s generally listed as “none, small, medium or large”, depending.
Some stones, especially old cuts, might have a culet that’s 1 1/2 mm
wide on a larger stone. What any of that has to do with making a
setting or setting a stone I do not know. All of the heights on a
stone are measured in a direct line, i.e.: put your gauge on the
culet and the table and that’s your measurement. Usually the
pavilion depth (from girdle to culet) is done with a ruler that’s
square to the plane of the stone, under magnification, because you
can’t lock a gauge on both of them. You do not measure a stone down
the angle of the pavilion from the girdle to the culet unless you’re
just curious - I guess you could use trig to figure it out that way,
too, if you wanted to… All the pertinent measurements are done
on an imaginary center line going from the center of the table to
the culet (for a round stone), and of course the girdle diameter.

http://www.donivanandmaggiora.com


#3

good book, much of the same info as her other books though so check
’em before buying more…( same with Elizabeth Olver’s books)
regarding the culet and pg.69: she means the culet ( bottom of the
stone) can vary if not machine cut, so measure all the stones and
don’t presume that each is the same DEPTH from girdle to tip as any
other in a parcel. IN her other book, “Jewelery Making”, she covers
the same thing a bit more clearly:

she says to take one diametric measurement just below the girdle,
and to measure the culet just above the tip…that drawing is much
more visually self-explanatory.

It shows the larger circle, in perspective about 3/.8 of an inch
above the smaller (culet’s) circle. When setting the stone in
anything but a flush setting it works out so that the stone is
comfortably resting on the bottom “ring” ( given a round brilliant
cut) or a bottom rectangle, for emerald cut,octagonal stones,
etc.thus the stones, in her methods of construction are set just
below the girdle in the top ring, and supported and leveled, with the
smaller ring just above the culet / tip -the two rings she shows
being connected by wires to construct the settings, and the addition
of prongs, or leaving the connecting wires to protrude 1/16th an inch
above the table of the stone for prongs.( the rules are different fro
her explanations of gypsy / flush setting) .I Find it very
interesting
that she uses inch measurements in her books, as opposed to
millimeters being British!!.

All-in-all I like her visual presentations of techniques and find
that students really like her books as they explain what many
teachers presume you come to class knowing…Coupled with Tim
McCreight’s book " the Complete Metalsmith"- any edition, and Harold
O’Connors " the Jewelwer’s Bench Reference", you should be mastering
setting skills in, uh, i don’t know…six months!!! But seriously, if
you are beginning, all three together are must haves as far as basics
and good references, explanations and standardization…after all you
probably want to develop consistency in the methodologies you choose
to learn well and enable yourself to repeat, after a time, without
having to go back to the marked pages… It will happen, be confident
of that…You are on the right track as it is, and Orchid, and a
number of other sites all provide you with many tools and
prescriptions for self-teaching… stone setting is the epitome of
your basic lessons…You may find it helpful to invest in some CZ’s
to practice with at first,especially the 1-3mm sizes and for pave
skill development, should you choose that as a desired application in
what you plan to do given your conceptualization of art, so that you
have perfected your skills to a point that you aren’t risking any
costly stones while learning them…On the other hand— there’s
always blue painter’s tape to cover a stone, in case a tool slips or
skips across the surface! R.E.Rourke

wish you would have asked on Orchid before ordering…, I happen to
have acquired 2 copies of McGrath’s “Ring Book” in the past two
years, and can only use one…C’est la Vie


#4

Hi Kelley,

I too was confused about the culet until I recently figured it out
(if I’m wrong, I’m sure someone will correct me). Take for example a
brilliant cut diamond. It can have 57 or 58 facets. The 58th facet is
the culet. If a culet (very small facet at the bottom of the diamond)
is not cut into the stone before the pavilion facets are cut, there
is a danger of the bottom point being chipped and thus ruining the
diamond. So, a small facet is cut and then the pavilion facets are
cut, hopefully so that there will be a lovely point at the bottom and
NO culet. However, sometimes a culet facet is left. Hopefully it will
be so small that it cannot be seen through the table of the stone but
sometimes (in a poorly cut diamond) the culet facet can be seen.

I hope that makes sense. So a stone may have a culet with an actual
diameter (hopefully tiny) or it may have none and come to a point.

As for the other measurement you mention, I’m not sure as I’ve not
yet purchased that book.

Regards,
Helen Hill