Extra
facets occur as additions to the normal number of facets on a brilliant.
They can occur anywhere on a stone but are usually found in the vicinity
of the girdle (Fig 323). They originate from the cutting away or
subsequent cutting away of small external feature. In contrast to
naturals, the surfaces of extra facets are just as flat and well
polished as all the other facets; they are bounded by straight edges
while those of naturals remain irregular as in nature.
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| Fig 319 very small extra facets on a pavilion girdle | Fig 320 very small extra facets on a pavilion main facet |
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| Fig 321 larger extra facet on a pavilion main facet | Fig 322 very small extra facet on a table facet (11 o'clock) |
| Natural crystal faces | Twinning lines |