Unusual Busticated Diamond

Wow! I haven’t seen this before. Lady shows me her damaged diamond,
typical but severe break that runs down pavilion from girdle. The
really weird thing, there was also a total even cleave across the
pavilion, parallel to girdle about half way down, the ‘new culet’ was
almost as big as the table! Louping it, I could see interference
colors, like its ready to break more. She’s taking it back to the
jeweler who sold it two months ago. Man, is he in for a shock.

Neil,

It sounds like the lady hit the stone in a direction parallel to a
cleavage plane, and she hit it hard enough to cleave the stone. This
would be damaged caused by her, not the fault of the jeweler, and
should be covered by her insurance, assuming she was smart enough to
buy a Personal Articles floater after having her ring independently
appraised.

She can “take it back” to the jeweler all she wants, but, absent any
guarantee in writing from him, she broke her diamond, that’s it.
Imagine buying a new car, running it into something and taking it
back to the dealer making demands.

Folks need to be responsible for their actions and they need to
insure their goods properly.

Wayne Emery

It sounds like it could be a doublet.

Dave Owen

As it has broken along its cleavage plane it will make recutting the
stone easier and less wasteful but someone is going to lose a lot of
money! Seen it happen on a largish industrial diamond in a point
hardness tester but never in a set stone. Any explanation as to how
it could have occurred from the customer?

nick

It sounds like the lady hit the stone in a direction parallel to a
cleavage plane, and she hit it hard enough to cleave the stone. 

right, of course, Wayne. But the described break IS unusual in one
important way. The direction of the cleavage plane in this stone was
close to parallel to the table of the stone, meaning the stone was
not oriented in the usual direction to the original diamond crystal.
This usually means a mishapen rough, a macle, or something of that
sort. Most of the time, the cleavage planes, which are paralell to
the octagonal faces of the usual octagonal diamond crystals, run
close to the pavilion angle, just a bit steeper than the pavilion
facets, and blows to the crown can flake off a cleavage running
girdle to culet. In this case, the cleavage plane is horizontal to
the stone, which would require different impact directions to do.
I’ve seen this sort of break mostly on small stones being pave set,
where the forces in just seating the stones, or tighteing beads, can
cleave stones oriented this way, but it doesn’t seem common in
larger stones. Among other things, the cleavage plane directions are
not only the easiest to break, but they are also the hardest to
polish, so cutters understandably try to avoid putting the table
facet along a cleavage plane or too close to it…

I agree with you that damage to the stone remains the responsibility
of the owner, or whomever was handling the stone when it broke. But
one should also keep in mind that perhaps, if it seems a given stone
was unusually prone to damage, that some leeway might be in order in
determining where the money to replace the stone can come from. This
situation of course is hard to evaluate, since in all likelyhood, the
stone did not present any obvious clues to it’s unusual orientation,
or the changed risks of breakage that might cause, so the jeweler
cannot easily be held responsible in terms of selling a stone more
likely to break (if that is even the case). But still…

cheers
Peter Rowe

My mother banged her diamond long ago. It took out a wedge like a 3-d
piece of pie that went from the girdle to the culet, all in one swell
foop. It was like 1/5 the weight of the diamond, which was 1/2 ct. or
something. Instant diamond abrasives…

http://www.donivanandmaggiora.com

Among other things, the cleavage plane directions are not only the
easiest to break, but they are also the hardest to polish, so
cutters understandably try to avoid putting the table facet along a
cleavage plane or too close to it... 

“hardest to polish” is a very optimistic. Next to impossible, would
be the term I use.

The degree of table polish is a critical observation in this case. In
any even, given unusual orientation, I would speculate that it was a
CVD diamond. Owner should submit stone to GIA, and if it is a CVD,
the jeweler may be responsible, depends on degree of disclosure he
provided.

Leonid Surpin.

I had a client years ago that was a former showgirl, and owned a
local bar. She wore a 2-3ct diamond in a 4 prong mounting that
probably had 9-11 separate cleaved areas on it, many probably from
banging it against the beer cooler.

Rick Hamilton

The diamond was set in a reasonably beefy four prong head. I could
see no way the pavilion could have been smacked. My first thought was
that the cleavage that ran down from the girdle, a most common
occurrence, somehow changed direction and cut across the pavilion.
Perhaps there was some glitchy thing going on at the particular point
where the cleavage plane (parallel to table) intersected the
developing chip. Maybe a laser drill hole? Of course though, this
brings into mind the crystal structure. If there was a cleavage
parallel to the table there shouldn’t be a plane roughly parallel to
the pavilion angle. Maybe it was a twinned crystal and the stress of
the chipping just pulled the two crystals apart? It was a very clean
surface on the ‘culet’ chip, almost looked polished.

As to responsibility of the seller…while he most likely had no
idea of the unusual potential for damage the seller may be in for a
hot time with the customer. The customer could argue she paid for, oh
what’s the legal term?..purpose suitability or something, I dunno.
Whether the seller knew or did not know about some theoretical
unsuitability, she bought it in good faith. Luckily the stone is
insured. But I wouldn’t want to have such a dispute land in my lap.
Anyway I thought it was weird enough to pass along for general info.
Could you imagine being the setter and have that happen? I wonder if
there is a way to inspect for a twinned crystal before setting.