A chalklike calx in the metallic-tree account

Meaning

The metallic-tree account calls for Gold to become a chalklike calx through a named historical water. Calx describes the resulting condition, while calcination names the transformation. The word does not here mean that the product is ordinary chalk. For other metals, the passage explicitly says calcination must be performed differently, leaving details to experience; that qualification prevents one universal operation from being inferred from the Gold example.