Lens edge chips are allowed only outside the clear aperture of the lens.
The clear aperture is 90% of the lens diameter unless otherwise specified.
Chips smaller than 0.5 mm are ignored, and those larger than 0.5 mm are
ground so that there is no shine to the chip. The sum of the widths of
chips larger than 0.5 mm cannot exceed 30% of the lens perimeter.
Prism edge chips outside the clear aperture are allowed. If the prism
leg dimension is 25.4 mm or less, chips may extend inward 1.0 mm from the
edge. If the leg dimension is larger than 25.4 mm, chips may extend inward
2.0 mm from the edge. Chips smaller than 0.5 mm are ignored, and those
larger than 0.5 mm must be stoned or ground, leaving no shine to the chip.
The sum of the widths of chips larger than 0.5 mm cannot exceed 30% of the
length of the edge on which they occur.
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