1,209. A Perforated, Peeled or Otherwise Damaged Esrog

Hilchos Shofar, Succah v’Lulav 8:7

If an esrog is perforated from one side to the other, it is invalid regardless of how small the hole may be. If a hole doesn’t go from one side to the other, then if it is the size of an isar (a small denomination of coin) or larger, the esrog is invalid. If even the smallest portion of an esrog is missing, the esrog is invalid. The pitom is a small protuberance from which an esrog flowers. If an esrog’s pitom has been removed, it is invalid. The stem of the esrog is from where it hangs from the tree. If the stem has been removed from an esrog, leaving a hole, it is invalid. If it an esrog gets covered with bumps in two or three spots, it is invalid. If it is covered with bumps in only one spot but that spot covers the majority of the esrog's surface, it is invalid. If a bump grows on even the smallest part of the pitom, it is invalid. Let’s say that an esrog is peeled without causing it to lose any of its body and it remains green (including yellow). In such a case, if the esrog has been completely peeled, it is invalid; if even the smallest portion of the peel remains, the esrog is valid.

Hilchos Shofar, Succah v’Lulav 8:8

An esrog is invalid if it is bloated, decayed, pickled, boiled, black, white, spotted or dark green like a leek. If an esrog is grown in a mold, causing it to be shaped like something else, it is invalid. If it retains the shape of an esrog, it is valid even though it was formed in layers. Two esrogim that grew connected and an unripe esrog are valid. In a place where esrogim naturally grow with a grayish shade, such esrogim are valid but if they are very dark, they are invalid everywhere.