If you are used to working with only faceted stones, you’ll
find that cabs and rose cuts are an entirely different animal. Very little of what you know transfers over
to the non-faceted gem world. Cab
pricing and weighs are different, they are judged on a different scale, and
most commercial settings don’t work.
First, be aware that cabs and rose cuts are not usually
clean gems. The facet grade rough is –
well – faceted, and cabs are the next grade down before rose cuts and then
beads. Cabochon material is therefore
rarely as clean as faceted stones. The
quality often ranges from very good (near facet grade) to very poor (totally
dead and opaque). Obviously, I don’t
recommend the latter. Cabs don’t have
brilliance either, rather, when set right, they glow, despite inclusions. Cabs usually rank better in terms of glow
than rose cuts because the facets of rose cuts don’t let the gem be as bright. And of course the term “window” doesn’t apply
because to not have window, you need back facets. Technically, therefore, all cabs and rose
cuts have window.
Spinel Rose Cuts |
When you buy cabochons, you can expect a lower per carat
price than for faceted stones, but you also need to expect them to weigh
more. On average, cabochons weigh twice
as much as faceted stones in the same size.
The exception are rose cuts, because they are flatter and the top facets
remove extra weight. The facets hide
flaws, however, so your expectations of a rose cut should be lower than that of
a cabochon. Rose cuts usually weigh
about the same as faceted stones. Often,
though, a high quality cab and a low quality faceted stones can come out the
same in terms of price.
Finding the right setting for cabochons can be
challenging. Even calibrated stones
often do not fit the settings that are fabricated for their size. Many are too high so that the bezel wall
doesn’t fold over right; or they are too low so that the stone vanishes under
the bezel wall. Yet others are slightly
too big or too small – the latter applies to rose cuts in particular. The smaller the cabochon, the more
problematic it is if it doesn’t fit right.
So when you choose cabs, watch for high dome and low dome, as the
terminology goes. If you have a bezel
already, bring it with you when you buy the stone and see how the stone looks
in it.
Round Commercial Bezels |
Add to that, that many cabochons are not calibrated in the
first place. So you have to expect to be
making the bezel by hand. This is even
more the case for rose cuts, which are often cut in irregular shapes, just
following the natural lines of the material.
The expectation is that for either, you will make your own setting, or
have it made.
When I make bezels for cabs and rose cuts, I usually do a
closed back. I find that many gems look
washed out when there is no metal behind them.
The light simply passes through them and that dulls the color. The exception, for me, is when I channel set
cabs for earrings, because then I like the light to pass through. A ring or a necklace has your skin behind it
at all times, and that doesn’t help the stone reflect out. In earrings, that is not a concern.
Square and Oval Cabochons, Cabochon Bullet |
Cabochons gemstones are very popular; Cabochon is not only used for making jewelry but also it is used for cure of many health related issues. Rose Cut technique can be dated back to the mid 16th century and is linked in with many historical cutting styles.
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