PLUMBUM. 63 $

But there is beside these another appearance of the ore of this metal, which is supe-rior to all other ores in beauty. This is a very firm and compact substance, of an evenand regular texture and considerable weight, and is sometimes found in large shapelessmasses, but not unfrequently in regular shoots. It is of a very bright and beautiful red,of a smooth even surface, and considerably pellucid, It resembles very much the na-tive Sandarach, and is sometimes exactly of the sine florid red of that body, thoughoften deeper, and sometimes approaching to a crimson but very rich in its tinge.

These are. the more usual and determinate appearances of Silver in the state of ore,but there are in regard to this as in all the other metals in the state of ore, numberlessaccidental variations, and there are Stones of all colours and consistences wrought indifferent places for the Silver they contain; as in the mines of Peru, some of the ores,as they are call’d, are grey spotted with blue and red, some of various shades of redwith admixtures of yellowish or brownish, and others green, yellow, or black. Someof these are of the nature of one or other of the former three, only debas’d by adven-titious mixtures; the others are Stones in which native Silver is lodg’d, which arecommonly confounded with the rest under the name of Silver ores.

We have some of the first appearance of Silver ore in England, which has been mi-staken for native lead, but there does not appear to be any great quantity of it;many of our lead ores contain Silver, and some in very large quantities; and Norwayand some parts of Germany have very considerable quantities, both of native Silverand that in the state of ore. The Hungarian Silver ores usually contain native Silverin form of small and slender filaments ; this is usually call’d capillary Silver, and thisas well as the native Silver of Peru, though found in Stones of various kinds, yet ismost frequently met with in a white opake Stone, usually call’d Spar, but really a de-bas’d Crystal, loaded with a large quantity of a white earth ; though sometimes it isalso found in genuine Spar.

. In some parts of Saxony the native Silver is also found in small flat spangles like thoseof Talc, and these often lodg’d flatwise in a coarse red Stone. And in many of the Ger-man mines the red pellucid and malleable black rich ores are found blended in thefame mass, and sometimes with the black wholly covering the red. The black ore ofthis kind is usually soft enough to be cut with a knife.

M E T A L L A.

Genus V.

j VlumbuituLead.

Lead is the heaviest of all metals except gold ; it is a metal which has been veryoften said to be found native, but the accounts seem erroneous. I have seen many spe-cimens of what was call’d native Lead, but never any thing that truly was so ; and amapt to believe, that what has been thought native Lead has always been either the blackSilver ore, or some more than ordinary pure pieces of Lead ore.

Lead in the state of ore is extreamly common, and no where rrtore so than in ourown kingdom, where it puts on various appearances, and makes an elegant figure inthe cabinets of the curious. These are, however, merely owing to accident in mostcafes, and the ore is much the fame in all.

There is indeed one general structure which runs thro’ the much greater quantity ofLead ores, tho’ being more distinguishable in some, and less so in others, even those ofthis kind have acquir’d different appellations. This structure is most distinguishable in whatare call’d the cubic or diced Lead ores; and the general conformation of these as well asmost others, is this, the mafles are all compos’d of angular bodies, much resemblingthe Spars of some kinds in their shape and structure, being of a shape either ap-proaching to a parallelepiped or regularly so, and these either thicker or thinner ones,and each compos’d as in the Spars of the fame shape of great numbers of very thinplates, which are themselves again compos’d of thinner parallellopipeds. These are thebodies that usually constitute Lead ores, and in some are more, in others less perfect.In those commonly call’d the cubic or diced Lead ores, and by many by a very inde-terminate