fish eye

He throws his dead fish eye up to me on what's left o' the bridge an' I felt my job was vacant.

When round these are called "pin-holes," and when slightly flattened "fish eye" openings.

Now you have not taken on "the evil eye" in coming to the bottom of the sea, but you have taken a "fish eye."

It had me casting the old fish eye around to see if everything was holding before I got through it.

A slightly spread stone is desirable, provided it has not lost brilliancy, and so become a “fish eye.”