The song is comparing the small white blooms of the lily of the valley to this coral jewelry.

That makes very good sense, leeneia! Now the question arises whether this points us to the USA, perhaps to Florida in particular? Were there other places where lyricists could assume such jewelry to be known?

(I remember the time when coral necklaces were fashionable in Europe, imported, of course, and always red or pink. I found them horrible, firmly associated to "maiden aunts without any understanding of little boys - and vice versa".)