For couering of Houses there are three sorts of Slate, which from that vse take the name of Healing-stones. The first and best Blew: the second, Sage-leafe coloured, the third and meanest Gray. The Blew, and so the rest, are commonly found vnder the walling Slate, when the depth hath brought the workmenn to the Water. This Slate is in substance thinne, in colour faire, in waight light, in lasting strong, and generally carrieth so good regard, as (besides the supplie for home prouision) great store is yeerely conueied by shipping both to other parts of the Realme, and also beyond the Seas, into Britaine and Netherland.
They make Lyme, moreouer, of another kind of Marle-stone, either by burning a great quantitie thereof together, with a seruent fire of Furze, or by maintaining a continuall, though lesser heate, with stone Cole in smaller Kils: this is accompted the better cheape, but that yeeldeth the whiter Lyme.
Touching mettals: Copper is found in sundrie places, but with what gaine to the searchers, I haue not beene curious to enquire, nor they hastie to reueale. For at one Mine (of which I tooke view) the Owre was shipped to bee refined in Wales, either to saue cost in the fewell or to conceale the profit.
Neither hath nature denyed Siluer to Cornwall, though Cicero excluded the same out of all Britaine: and if wee may beleeve our Chroniclers reports, who ground themselues vpon authenticall Records, king Edward the first, and king Edward the third, reaped some good benefit thereof. But for our present experience, what she proffereth with the one hand, shee seemeth to pull backe with the other, whereof some Gentlemen not long sithence, made triall to their losse: howbeit, neither are they discouraged by this successe, nor others from the like attempt.
Tynners doe also find little hoppes of Gold amongst their Owre, which they keepe in quils, and sell to the Goldsmithes oftentimes with little better gaine, then Glaucus exchange.
Yea it is not altogether barren of precious stones, and Pearle: for Dyamonds are in many places found cleauing to those Rockes, out of which the Tynne is digged: they are polished, squared, and pointed by nature: their quantitie from a Pease, to a Walnut: in blacknesse and hardnesse they come behind the right ones, and yet I haue knowne some of them set on so good a foile, as at first sight, they might appose a not vnskilfull Lapidarie.
The Pearle (though here not aptly raunged) breed in bigge Oysters, and Muscles, greater in quantitie, then acceptable for goodnesse, as neither round nor Orient. Perhaps Caesar spoyled the best beds, when he made that gay Coate of them, to present his graundame Venus.
Cornwall is also not altogether destitute of Agates [8] and white Corall, as by credible relation I haue learned.
But why seeke wee in corners for pettie commodities, when as the onely mynerall of Cornish Tynne, openeth so large a field to the Countries benefit? this is in working so pliant, for sight so faire, and in vse so necessarie, as thereby the Inhabitants gaine wealth, the Merchants trafficke, and the whole Realme a reputation: and with such plentie thereof hath God stuffed the bowels of this little Angle, that (as Astiages dreamed of his daughter) it ouerfloweth England, watereth Christendome, and is deriued to a great part of the world besides. In trauailing abroad, in tarrying at home, in eating and drinking, in doing ought of pleasure or necessitie, Tynne, either in his owne shape, or transformed into other fashions, is alwayes requisite, alwayes readie for our seruice: but I shall rather disgrace, then endeere it by mine ouer-weake commendation, and sooner tire myselfe, then draw the fountaine of his praises drie. Let this therefore suffice, that it cannot bee of meane price, which hath found, with it, Dyamonds, amongst it Gold, and in it Siluer.
The Cornish Tynners hold a strong imagination, that in the withdrawing of Noahs floud to the Sea, the same tooke his course from East to West, violently breaking vp, and forcibly carrying with it, the earth, trees, and Rocks, which lay any thing loosely, neere the vpper face of the ground.