Update: I want to link to a recent post Berta made comparing 3 books of correspondences side by side. I think it’s a good addition for anyone interested in this topic.
I agree with the points made here. Correspondences are very personal and you can make your own:
If upon seeing a new plant/herb/crystal, it immediately tells you something (e.g. purple = spiritual awakening), then that’s going to be the correspondence that works for you, and nobody can tell you whether it’s right or wrong.
The ones in books are probably of a more traditional character or even accidental discoveries. You can see an example of this in the Philosophy of Natural Magic, by Henry Cornelius Agrippa: (Chapter XXIV)
" These things are Lunary, amongst the Elements, viz.: The earth, then the water, as well that of the sea as of the rivers; and all moist things, as the moisture of trees and animals, especially they which are white, as the whites of eggs, fat, sweat, phlegm, and the superfluities of bodies. Amongst tastes, salt and insipid; amongst metals, silver; amongst stones, crystal, the silver marcasite, and all those stones that are white and green. Also the stone selenite ( i. e. , the Moon, Lunary), shining from a white body, with a yellow brightness; imitating the motion of the Moon, by having in it the figure of the Moon, which daily increaseth or decreaseth as doth the Moon. Also pearls, which are generated in shells of fishes, and stalactites, formed from the droppings"