It is sad to admit, but many Jewelers & Antique Dealers
who handle diamonds daily, interchange
the two "names" without truly
understanding the difference between these two styles of
cutting, and their many "transitions" along
the way. Starting with the "Old Mine Cut", with its
square shape and slowly changing to the "Old
European Cut" with its round shape. By
studying the cutting style of
the diamond, one can determine the
actual circa (with in a few years), that the diamond was
actually cut from the rough. The descriptions below will
give you a better understand these differences.
Because there are actually six (6)
different periods between early Old-Mine-Cut diamonds
and the Modern-Brilliant-Cut diamonds, by understanding
these gradual transitions of diamond cutting over a 100
year period, one can more accurately assign a proper
circa to the item of jewelry based on the diamonds in
the item and their cutting style.
q Old Mine Cut =
(There has always been argument about the origin of
the name, some say it is derived from the Old-Mines from
India, others say it's name comes from the Old-Mines in
Brazil). An Old-Mine-Cut is one of the oldest
cutting styles, is somewhat
square in
shape, has a small table, no point on the culet
and the culet could be
off center. That is to say that the diamond
generally has the same shape as the original crystalline
structure of the diamond when it was in the rough,
(Rather square in appearance)
q Late Transitional Old Mine Cut
= The same as above but with some rounding
of the girdle, small table, no point on the culet and it
may or may not be centered, (Getting
a bit rounder, but still somewhat square)
q Early Transitional Old European Cut
= Almost a round girdle but not perfectly round at
this point,
small table, no point on the culet and almost centered.
That is to say that this diamond has all the
cutting characteristic of an Old European Cut Diamond,
except that it is not fully round, as an Old
European Cut should be. The girdle
“almost round”, but it shows a bit of the
“square-shape” that is normally associated with an
Old Mine Cut Diamond. Thus its classification is an Early
Transitional- Old European Cut, a period of
cutting and time when diamond cutting was making the
transition from Old Mine Cut to Old European Cut.
("Almost Round, but not actually round")
q Old European Cut =
Round in shape, small table, no point on the culet and it should
be relatively centered. (At last
the Diamond is Round)
q Late Transitional Old European Cut
= A round girdle, the table is getting wider, and
the culet may have a point or almost a point and be
centered. The transition of cutting is approaching the
modern brilliant cut, but the diamond does not
have the mathematical proportions to be classified as a
modern brilliant cut, a period
of cutting and time when diamond cutting was making the
transition from Old European Cut to an Modern Brilliant
Cut. (Round, and the table is
still a bit small)
q
Modern Brilliant Cut = A
round girdle, the depth is 57.0 to 63,0%, the table is a
53.0 to 66.0 % of the width, the pavilion depth is 41.5
to 45.5%, the crown height should be 11.0 to 16.2% of
the overall depth, and the crown angle is 30.0 to 35.0
degrees. There should be a good point on the girdle and
it should be centered.
(Gemological Cutting Perfection)
~~~~~ ~~~~~
~~~~~ ~~~~~
Another basic
explanation:
Square in shape
=
Old Mine Cut Diamond. If the diamond has a
somewhat square shape and the culet (the
diamond point) does not come to a point it is an
Old Mine Cut Diamond.
Round in shape
=
Old European Cut Diamond. If the diamond has a round
shape, with a small table and the culet
(the diamond point) does not come to a point, it
is a Old European Cut Diamond.
~~~~~ ~~~~~
~~~~~ ~~~~~
I hope the above explanation is helpful in understanding
the difference between these two diamond cutting styles
that relate directly to the period of when a particular
diamond was cut. With this knowledge, one can
properly assign an proper circa for that particular
diamond. Since diamonds in many cases are re-set
into other pieces of jewelry, as a result there are
times when an item can have several different ages
assigned to that same item of jewelry.
Other older cutting styles, that
should not be confused with Old-Mine-Cuts, are
the Brazilian-Cuts and the Lisbon-Cuts, Single-Cuts &
Rose-Cuts. Though at the first glance (To the un-trained
eye) they may appear to be the same, but there is a vast
difference between these four cutting styles. To often
people interchange these 4-catogories of diamond cutting
and improperly identify the cutting style, thus falsely
representing the item of jewelry and its probable circa.
In no way should these three cutting styles (Above) be
confused with the two Old-European-Cuts or
English-Round-Cut-Brilliant, shown below.
~~~~~~ ~~~~~ ~~~~~
~~~~~
Other Diamond Cutting Styles
Another group of Diamond-Cutting Styles that many
people confuse with Old-Mine and Old European Cut are
Single-Cut Diamonds and Rose-Cut Diamonds.
Single-Cut Diamonds have the same shape as
full-cut diamonds, but generally have 1/2 the amount of
facets as a full-cut diamond.
Rose-Cut Diamonds are a bit like a pie-pan
flipped up side down in their shape, that is to say that
there are facets on the top of the stone, but they are
flat on the back side (See the side view's below).
I hope that the description and drawings
have helped you in understanding the difference between
the various diamond cutting styles, epically with
antique & estate jewelry. To often many inexperienced
"dealers" improperly interchange the identification of
the diamond cutting style and use the wrong name for the
diamonds in that item, thus misrepresenting that item of
jewelry as well as assigning the wrong circa for that
item because inadequate knowledge and experience.
Hopefully this information provided here will better
inform buyers as well as sellers, when purchasing
antique & estate jewelry.
Walt Tofel
"Your Master Jeweler"
There are many
cutting-styles that may give good guidance to the period
of when the diamond was cut, below are only a few of
many cutting styles that you may find in antique &
estate jewelry.
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