This is my take on it.
With pear shapes you have the point and then the rest of it. With
hearts you have the point and the cleft and then the rest of it. I’ll
come back to that.
Starting with pears in prongs here. When you set the stone you will
be nestling it down into your seat (which you have already cut). You
could set the heel first and then nestle the point down into its
seat. Trouble is this may put a lot of pressure on the point, the
most easily damaged part of the stone. Keep in mind that the point
prong is often a V prong that is at an angle when viewed from the
side. The deeper you nestle the point, the closer into the main body
that portion of the prong gets, the more pressure you put on the
point. OR, the deeper you nestle the point, the further towards the
heel you shove the stone.
If you have cut the seats a bit uneven (sometimes its hard to tell
just by looking, Pears often have a deep belly and slight differences
between left and right make a big difference in how the stone seats
in the prongs), by setting the point last you can make NO adjustments
to try to correct this misalignment.
I like to cut the point seat first. I have no formula for how high
up the V prong to make it, I just eyeball it. But generally I lay the
stone in the uncut prongs, note the relative position of the girdle,
then figure the stone will come down anywhere from one to two MM,
depending. Depending on what, he said? My answer is, depending on a
lot of considerations that you’ll eventually get the hang of.
OK, the point seat is cut. Next tentatively pinch in the walls of
the V prong enough to form a stop. Lay the stone back in and the
point will rise no further up the prong than where you made the stop.
This is your reference point for all further seat cutting. You will
bring the seats lower, a little bit at a time till the stone sits
level and true and firm from all angles. Got it just right? Good, go
ahead and bend the prongs and finish it off.
Hearts. Here you have the extra complication of the cleft. Which
means you have TWO constant points to anchor. If your setting has a
prong actually IN the cleft it gets tricky. Cut point and cleft seats
first, paying close attention to level when viewed from the side.
Again, cut and fit, cut and fit. A slight bit of extra prong pressure
can tilt it out of whack noticeably. so pull all prongs in a little
bit at a time. This allows you to make corrections before its too
late. You may have to pull the stone in order to make a correction
cut on a prong. However, once the prong bends X amount you may not be
able to pull the stone without some major distortion of the work
you’ve done to this point. If there is no prong in the cleft just
handle it like a pear. Anchor the point, level down to that point.
Bezels. Life is a little simpler here.
On a pear, I would still start at the point, but for an additional
reason. And that is slack in the bezel. With a round or oval stone,
there is no single concentration point for slack. Some people might
describe it as excess metal. You are basically making a larger
perimeter smaller so you wind up with slack material, its gotta go
somewhere. On a pear if you start your bezel pushing at the heel, by
the time you get to the point you’ve got a considerable amount of
slack with no where to hide it…ugly point. But if you start your
pushing at the point you have the whole rest of the stone to
compensate. Nail down the point, then move to the heel directly
opposite, then mush your way at each of the clock hours in such a way
that you’re not accumulating slack. That’s probably not the clearest
way to explain it, sorry.
Heart in a bezel. This is tricky. You have your two anchor points
BUT you may find that when you push the bezel at the shoulders your
cleft pops out! In this case I would consider starting at the point
and rolling your way along, sequentially so to speak, so that you
deliberately accumulate slack that you can then ‘stuff’ into the
cleft. This is very dependent on the particular stone. The fatter the
belly and/or rounder the cleft, the more it tends to pop out the
cleft. Bear this in mind when selecting stones.
Simple. One, two, three, right? Yeah, take your coffee break now.
Please note, No voodoo or rocket science was used in the making of
this post. Analyze what’s happening as you explore your way along.