The dominions of Great Britain abound in as great variety of minerals, perhaps, as any country whatever, of the same extent. [electronic resource] : And, though we have not yet discover'd any Gold or Silver Mines, (properly so call'd;) yet 'tis probable there may be such; and both those Metals are extracted out of other Metals, especially Silver from Lead, as good as any in the World: And, if good Encouragement is given, the Mines that are already discover'd may be, not only effectually carry'd on and improv'd, but much greater Discoveries may be made, and more abundance of Silver produc'd, than is at present; several Persons having, by their Study, Industry, and Learning, arriv'd to great Skill and Perfection in the Art of Melting and Refining Metals.