Is a lechi that was not placed intentionally as a lechi but appeared on its own valid?

Synopsis

A naturally occurring lechi is valid provided one relied on it before Shabbat. If another lechi was in place and fell on Shabbat, one may not then rely on the naturally occurring one.

Early Acharonim
Late Acharonim
Lenient
Strict
Lesser cited
Major authority

Discussion

Discussion coming soon.

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