The manner of trying minerals hath been already made known, wherefore it is not needful here to write many things, because divers Authors, as _Georgius Agricola_, _Lazarus Ercker_, and others have sufficiently wrote thereof, to whose writings I refer thee, especially to that most famous _Lazarus Ercker_ which is so much commended, _De Probatione Mineralium_, as well maglignant (obstinate) as mild. But thus much know, being that which experience hath also taught us, that neither he nor his predecessours had a perfect knowledge of all things, nor would reveal all things they knew. For many excellent things do yet lye hid, and perhaps shall yet for a while lye hid by reason of the ingratitude of the world; although the most famous Philosophers do with one consent affirm that imperfect metals, as lead, tin, iron, copper, and Mercury, are intrinsecally gold, and silver, although it may seem very improbable to many that are not curious, but contented with the opinions of their parents; supposing those minerals to be barren that leave nothing in the cuple, when they are tryed with lead: when as yet that proof by cuples although famous, is not yet that true Philosophical trial of metals, but only vulgar, according to the testimony of Philosophers, as of _Isaac Hollandus_, and others, especially of _Paracelsus_ in many places treating of metals, but especially in his book _Vexationum Alchymistarum_, containing a true description of the properties, and perfection of metals. Which although not being to be understood by all, matters not; for a very easie art is not to be communicated to all, according to _Paracelsus_ saying. Imperfect metals being freed from their impurities have in them abundance of gold, and silver. But how metals are to be purged, and separated he doth not teach, but only commends _lead_ to be the Author; which made the Alchymist believe that it was common lead, not knowing that the water thereof (lead) did not only purge other metals, but also lead it self; supposing also that the trial of tin, copper, and iron, made in a cuple with lead to be that true genuine bath thereof; not observing that lead hath no affinity with iron, and tin in a stronger fire, but to reject what is black, and unclean, without any perfection. Now this lead can do, if _viz._ it be mixed with a mineral that hath gold or silver in it, and be melted in the fire being incorporated with it, it may together with their impurities enter into the Cuple, the good gold and silver being left in the Cuple, which is the proof of minerals that are digged, and used; and it is done upon this account, _viz._ gold and silver may be naturally purged of their superfluous sulphur, so as never to be any more radically united, and mixed with those that be imperfect, as being polluted with abundance of crude, impure sulphur, although they may be melted together in the fire; yet that mixture being retained in the fire, the combustible sulphur of