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Table Star/ Upper main facet |
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 |
Upper
girdle facet |
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| Girdle |
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| Lower
girdle facet |
| Lower
main facet |
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Culet |
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When a stone is cut according |
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|
| to
good proportions, the light is |
If the stone is cut too thick, |
If the stone is cut too much flat,
the |
| reflected from one facet to
another |
part of the light escapes |
light escapes from it before to
be |
| and arises by the top. |
outside downwards. |
returned on another facet. |
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 |
 |
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USUAL PROPORTIONS .
 |
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Designation of diamond's quality. |
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|
TW:
Top Wesselton |
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| IF: |
TW
VVS: |
TW
VS |
TW
SI |
| Internally
flow
less |
Very
Very small incl. |
Very
small incl. |
Small
incl. |
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| Coloured
stones |
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| FL |
NFL |
LI1 |
LI2 |
MI1 |
 |
 |
 |
 |
 |
| Flaw
less |
Near
flaw less |
Lightly
included 1 |
Lightly
included 2 |
Medium
included 1 |
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| MI2 |
MI3 |
VI1 |
VI2 |
HI |
 |
 |
 |
 |
 |
| Medium
included 2 |
Medium
included 3 |
Very
included 1 |
Very
included 2 |
Highly
included |
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| PRINCIPAL
COLORING ELEMENTS IN THE GEMS. |
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|
| Chromium |
Ruby,
Emerald, Pyrope garnet, grossularite and uvarovite, Tourmaline. |
| Copper |
Dioptase,
Malachite, Azurite. |
| Iron
|
Sapphire,
Aquamarine, Citrine, Almandin garnet. |
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| Manganese |
Morganite,
Pink tourmaline, Spessartite garnet. |
| Nickel |
Chrysoprase. |
| Titanium |
Blue
Sapphire. |
|
Vanadium |
Green
beryl, Blue zoïsite , Garnet. |
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 |
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| Mechanical
cutting. |
Mechanical
shaper. |
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| ©
All of
the pictures on this site have been shot by Darbel du Bourg. |
|
