Crystals and precious stones are the quintessence of the earth. Flowers are the quintessence of water.

Birds are the quintessence of air. Initiates, who represent the Deity on earth, are the quintessence of fire.

And finally, beyond fire, the quintessence of ether, that is to say, the quintessence of all these quintessences, is the angelic host that reaches up to God, this whole hierarchy of beings that Jacob saw in his vision going up and down the ladder between earth and the Throne of God.
The Scriptures say that man must become a jewel in the crown of God. This is a symbol.

Precious stones are attached to the earth and are nourished by the earth; flowers cannot live without water; birds dwell in the air, and human beings die if they are not in contact with fire. Fire is the food of the initiates.

When Zoroaster asked the god Ahura-Mazda what primordial man ate, Ahura-Mazda replied, ‘He ate fire and drank light.’

Omraam Mikhaël Aïvanhov