Can anyone tell me how to differentiate a DIAMOND vs. MOISSANITE
using only a 10x loupe and the naked eye. Any shared
will greatly be appreciated.

  • Lisa -


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Hi, Check for doubling of back facet along pavilion facets.
Moissanite give a double refractive index. This can be achieved
by looking (with a 10x loupe) through the bezel facet and on to
the pavilion facets.

Good luck.


Dr. E. Aspler
Managing Director
Ganoksin Jewelry Co.,Ltd

Webmaster Ganoksin Online

ICQ # 864 5224

Haven’t seen one yet myself, however the experts (GIA et.
al.)say that if you view one in a direction more or less parallel
to the table through the girdle facets, you should be able to see
doubling of the opposite facet edges due to syn. moissonite being
doubly refractive whereas diamond is SR.

The most obvious one is that moissanite is double refractive,
while diamond is singly refractive. This is easy to detect. So
easy, that once I saw the side by side photos of the two I
wondered what all the fuss was about. When you look into
moissanite, the facets on the bottom will reflect twice as many
as there actualy are – doubly refractive.

Chicago, IL, US


I haven’t actually seen Moissanite, so I can’t tell you this from
actual experience, but based on what I’ve seen in JCK and through
GIA, Moissanite is doubly refractive.

If it’s cut correctly, it will face up as singly refractive
like a diamond, but tilt it just off that axis and you should be
able to see doubling in the facet pattern. This should be very
clear in a 10x loupe.

Can someone who’s actually seen Moissanite tell me if the
doubling is strong (like peridot or zircon) or weaker?


Kat Tanaka

I have viewed MOISSANITE using a 10x loupe and there are two
characteristics that distinguish it from a diamond. It is
double refractive, by looking from the top through one of the
crown facets you will see two culets and a star effect. The
stones that I viewed had some small pin line tubes that appeared
to run from the girdle to under the crown. Almost like
irregular laser drill tubes. The mounted stones are the ones that
frighten me, one must rely on sales people to determine the type
of stone at the time of take in for repair. Our GG is helping
educate our staff regarding diamond simulates. I would expect
that pawn shops will see more of the stones than the average
jewelry store.


Roger Kitchens

 Can anyone tell me how to differentiate a DIAMOND vs.
MOISSANITE  using only a 10x loupe and the naked eye.  Any
shared will greatly be appreciated.

Moissanite is doubly refractive, while diamond singly
refractive. By carefully looking through the table at the facet
junctions near the culet you should see a doubling of the facet
junctions. The junctions may look a little out of focus, instead
of seeing just 1 junction, there’ll be 2 of them, parallel to
each other.

In the event the stone wasn’t oriented to show the doubling
through the table, observe the facet junctions from different
angles, always looking through the stone to a facet junction on
the opposite side. The doubling will always be there on some


Hello Lisa,

Diamond properties :

  • hardness : 10
  • SG : 3.50

Synthetic Moissanite properties :

  • hardness : 9.25
  • RI : 2.65 to 2.69 , DOUBLY REFRACTIVE
  • SG : 3.20

Two characteristics of synthetic moissanite :

  • it is doubly refractive, diamond is singly refractive. With a
    gemmological microscope or a loupe examine the stone through the
    table top and crown facets, the facet junctions on the other side
    (pavilion) of the stone will appear to be double for the
    synthetic moissanite. The doubling of the back facets will give a
    slight fuzzy appearance to the synthetic moissanite compare to
    the one of diamond.

  • it does have white ribbon-like inclusions, which run parallel
    to each other, but do not show any fractures.

For more infos on Synthetic Moissanite, got to the “Orchid

Best Regards,


Moissionite is reported to be strongly doubly refractive, so you
should be able to see a double image on the back facets by
looking thru the table. Haven’t actually seen one yet though.

Visit Brenn Jewelers website at

Brenny McLaughlin/Brenn Jewelers
4714-C Starkey Rd.
Roanoke, Va. 24014
voice 540-776-9654
fax 540-776-6342

Lisa: From all the samples of moissanite I have seen, they look
very dark and lack much of the fire of a diamond. You may or may
not be aware that there are electronic devices to detect them.
However, I think this poor imitation of a diamond with the funny
name will fade away as a simulant.

In my humble opinion, I remain yours truly; Steve Klepinger

Hello Lisa:

A new diamond imitation, synthetic moissanite (silicon

carbide), is now being produced by C3 Inc. in near-colorless form
for jewelry purposes. With refractive indices of 2.648 and 2.691,
a dispersion of 0.104, a hardness of 9=BC on the Mohs scale, and a
specific gravity of 3.22, synthetic moissanite is much closer to
diamond in overall appearance and heft than any previous diamond
imitation. The thermal properties of synthetic moissanite are
also so close to those of diamond that the thermal probes
currently on the market react to synthetic moissanite as if it
were “diamond.” This new material can be readily separated from
diamond on the basis of its anisotropic optical character, which
produces a doubling in the appearance of facet junctions. A new
instrument manufactured by C3 Inc. solely to distinguish
synthetic moissanite from diamond was also examined for this

This was taken from the Gems and Gemology home page.

Michael Mathews Victoria,Texas USA

Another method although not fool proof is to look at the girdle
of the stone. Moissanite will have a polished girdle. Not a
faceted but a polished. Some diamonds will be found this way but
it is very rare.

Moissanite will also be cut much shallower than a diamond will
be. I have seen quite a few samples, the largest being a 5.5mm
stone. It does look fairly good but they are having production
problems getting anything higher than an I color. To be perfectly
honest with you I don’t see it as a big deal to those who are

Chuck@ C.H.& Co.

The material you will see on the market is synthetic moissanite
and you should be careful to refer to it that way. While
moissanite does occur naturally it is not found in quantities
which can be of use to anyone in the jewelry industry. It was
actually first discovered on a meteorite.

To answer your question, you can tell the difference with a 10x
loupe relatively easily in larger stones, and with a little more
effort on melee. Synthetic moissanite is doubly refractive,
whereas diamond is singly refractive. This translates into a
doubling of the facet junction lines when the pavilion is viewed
through the crown. The most obvious effect is noticed when you
view the culet through a bezel facet. You can purchase samples
of syn. moissanite directly from C3 (the manufacturer). I have
a 3mm and a 5mm on hand to review occassionally so I can become
comfortable at distinguishing it from diamond.

There are also testers on the market. I have only seen the one
made by C3 and was not thrilled when I saw someone using it and
the tester indicated that the syn. moissantite was a diamond. If
I understand it correctly, the tester uses optics to distinguish
the two, and if the stone is not held correctly, you can get a
false reading. I personally would rather see an idiot-proof

I finally had the opportunity to view a number of
synthetic moissanites. No way would I mistake them for
diamonds,even without a loupe. They were pretty enough, but
much too refractive. I think a well-cut CZ is more
diamondlike than a moissanite.

of the stone. Moissanite will have a polished girdle. Not a
faceted but a polished. Some diamonds will be found this way but
it is very rare.

After viewing a couple of moissanites, I made the same
observation about the polished girdles. In fact I bet $100
the another party couldn't find a truly polished girdle in a
month. This happened a little over a month ago. He didn't
produce the required stone. I currently have in my possession
a tennis bracelet with 30/ .25ct diamonds. Several have a
highly polished and not faceted girdles. There are also some
with faceted girdles, but the point is that highly polished
girdles are becoming more common. A stupid bet on my part.
Another observation was that the moissanites were noticiably
more dispersive.    

Bruce D. Holmgrain
e-mail: @Bruce_Holmgrain
phone:: 703-593-4652

       They were pretty enough, but much too refractive. I
think  a well-cut CZ  is more diamondlike than a moissanite.  

I saw a couple of synthetic moissanite a couple of weeks ago and
I think the word we are looking for here is dispersive. Reminded
me of strontium titanate. Facet edges were very sharp. Diamond
like. I guess the color ranged somewhere around N-P.

Bruce D. Holmgrain
e-mail: @Bruce_Holmgrain
phone:: 703-593-4652

Moissanite can be distinguished by double refraction. I have
some pictures up on my site at It is not easily seen through
the table because of orientation. Tilt the stone and look
through a main facet at an angle. facets on the other side of the
stone appear doubled. Takes a little practice but once you know
what to look for it is easy. Jim