Translations:Adventist Youth Honors Answer Book/Nature/Shells/32/en
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Technically speaking, under the right set of circumstances almost any shelled mollusk can produce some kind of "pearl". However, most molluscan "pearls" have no luster or iridescence. In fact, the great majority of mollusk species produce pearls which are not attractive to look at, and not durable, such that they usually have no value at all, except perhaps to a scientist, or as a curiosity.
