Essay Natural History of the Earth and Minerals – John Woodward


PART IV. Of the Origin and Formation of Metalls and Minerals.

What I can advance, with com∣petent Certainty, about the Fluids of the Globe: the Sea, Springs, Rivers, and Rain, I propose in the immediately foregoing, or Third Part of this Essay: As in the Second Part of it I dispatch the Solids: Stone, Marble, Gravel, and all the other Terre∣strial Matter of it, which is digested into Strata. That Part therefore com∣prehends the far greater share of that Matter; and indeed all, excepting on∣ly Metalls and Minerals; which are found much more sparingly and in lesser Parcels; being either enclosed in those Strata (lying amongst the Sand, Earth, or other Matter whereof they consist) or contained in their perpen∣dicular Fissures. And these remaining still to be considered, I have allotted this Fourth Part to that Purpose.

To write of Metalls and Minerals intelligibly and with tolerable perspi∣cuity, is a Task much more difficult than to write of either Animals or Ve∣getables. For these carry along with them such plain and evident Notes and Characters either of Disagreement, or Affinity with one another, that the several Kinds of them, and the subor∣dinate Species of each, are easily known and distinguish’d, even at first sight; the Eye alone being fully capable of judging and determining their mutual Relations, as well as their Differences.

But in the Mineral Kingdom the Matter is quite otherwise. Here is nothing regular, whatever some may have pretended: nothing constant or certain: insomuch that a Man had need to have all his Senses about him: to use repeated Tryals and Inspections, and that with all imaginable Care and Wariness, truly and rightly to discern and distinguish Things, and all little enough too. Here is such a vast va∣riety of Phoenomena, and those, many of them, so delusive, that ’tis very hard to escape Imposition and Mistake.

Colour, or outward Appearance, is not at all to be trusted. A common Mar∣casite or Pyrites shall have the Colour of Gold most exactly: and shine with all the Brightness of it, and yet upon tryal, after all, yield nothing of worth, but Vitriol, and a little Sulphur: whilst another Body, that hath only the Resemblance of an ordinary Peble, shall yield a considerable quantity of Metallick and valuable Matter. So likewise a Mass, which, to the Eye, appears to be nothing but meer simple Earth, shall, to the Smell or Taste, discover a plentiful Admixture of Sul∣phur, Alum, or some other Mineral.

Nor may we with much better Se∣curity rely upon Figure, or external Form. Nothing more uncertain and varying. ‘Tis usual to meet with the very same Metall or Mineral, naturally shot into quite different Figures: as ’tis to find quite different kinds of them all of the same Figure. And a Body, that has the shape and appearance of a Diamond, may prove, upon▪ Exami∣nation, to be nothing but Crystal, or Selenitis: nay perhaps only common Salt, or Alum, naturally crystallized and shot into that Form.

So likewise if we look into their Si∣tuation, and place in the Earth; some∣times we find them in the perpendicu∣lar Intervalls: sometimes in the Bodies of the Strata, being interspers’d amongst the Matter whereof they consist: and sometimes in both; even the gemmeous Matter it self, (if I may so speak) with this only difference, that those Gemms, e. g. Topazes, Amethysts, or Emeralds, which grow in the Fissures, are ordinarily crystallized, or shot into angulated Figures: whereas in the Strata they are found in rude Lumps, and only like so many yellow, purple, and green Pebles.

Not but that even these that are thus lodged in the Strata are al∣so sometimes found crystallized †, and in form of Cubes, Rhombs, and the like *. Or if we have respect to the terrestrial Matter wherein they lye in those Strata, here we shall meet with the same Metall or Mineral embodied in Stone, or lodged in Cole, that elsewhere we found in Marle, in Clay, or in Chalk ‖.

As much Inconstancy and Confusion is there in their Mixtures with each other, or their Combinations amongst them∣selves; for ’tis rare to find any of them pure, simple, and unmixt: but Cop∣per and Iron together in the same Mass: Copper and Gold: Silver and Lead: Tin and Lead: yea sometimes all the six promiscuously in one Lump. ‘Tis the same also in Minerals; Nitre with Vitriol: Common Salt with Alum: Sulphur with Vitriol: and sometimes all five together.

Nor do Metalls only sort and herd with Metalls in the Earth: and Minerals with Minerals: but both indifferently and in common together: Iron with Vitriol, with Alum, with Sulphur: Copper with Sulphur, with Vitriol, &c. yea Iron, Copper, Lead, Nitre, Sulphur, Vitriol, and perhaps some more in one and the same Mass.

In a word, the only standing Test, and discriminative Cha∣racteristick of any Metall or Mineral must be sought for in the constituent Matter of it: and it must be first brought down to that before any cer∣tain Judgment can be given.

And when that is once done, and the seve∣ral kinds separated and extracted each from the other, an homogeneous Mass of one kind is easily distinguishable from any other: Gold from Iron: Sul∣phur from Alum: and so of the rest. But without this, so various are their Intermixtures, and so different the Face and Appearance of each, because of that Variety, that scarcely any thing can be certainly determined of the particu∣lar Contents of any single Mass of Ore by meer Inspection.

I know that by Experience and Conversation with these Bodies, in any Place or Mine, a Man may be enabled to give a near Conje∣cture at the Metallick or Mineral In∣gredients of any Mass commonly found there; but this meerly because he hath before made tryal of other like Masses, and thereby learned what it is they contain. But if he remove to another place, though perhaps very little distant, ’tis ten to one but he meets with so different a face of Things, that he’ll Page  176 be there as far to seek in his Conjectures as one who never before saw a native Ore, untill he hath here made his try∣als as before, and so further informed himself in the matter.

Metalls being so very useful and ser∣viceable to Mankind, great Care and Pains hath been taken, in all Ages, in searching after them, and in separa∣ting and refining of them. For which reason ’tis that these have been accu∣rately enough distinguish’d, and redu∣ced to six kinds, which are all well enough known.

But the like pains hath not been taken in Minerals; and therefore the Knowledge of them is somewhat more confused and obscure. These have not yet been well reduced, or the number of the simple original ones rightly fixt; some, which are on∣ly Compounds, the Matter of two or more kinds being mix’d together, and, by the different Proportion and Modu∣lation of that Matter, variously dis∣guised and diversifyed, having been reputed all different kinds of Minerals, and thereby the Number of them un∣necessarily multiplied.

Of this we have an Instance in the Gemm-kind; where, of all the many sorts reckoned up by Lapidaries there are not above three or four that are Original; their Diversities, as to Lustre, Colour, and Hardness, arising from the different Admixture of other adventitious Mineral Matter. But the farther and clearer Adjustment of this Affair I am constrained to adjourn to the larger Treatise.

In the mean time ’tis sufficient for my present▪ Design, to remark in gene∣ral, that those Minerals and Ores of Metalls which are reposited in the Bo∣dies of the Strata, are either found in Grains, or small Particles, dispersedly intermix’d with the Corpuscles of Earth, Sand, or other Matter of those Strata: or else they are amass’d into Balls, Lumps, or Nodules.

Which Nodules are either of an irregular and un∣certain Figure, such as are the common Pyrites: Flints, Agates, Onyx’s: Pebles, Cornelions, Iaspers, and the like: or of a Figure somewhat more regular and observable, such as the Belemnites: the several sorts of Mineral Coral, of the Stelechites, and of the Lapis Mycetoides‖: the Astroites, or Starry-Stone, as well that sort with the Prominent, as that with the Concave Stars: the Selenites: the Echiated Crystalline Balls, with many more analogous Bodies.

Those which are contained in the Perpendicular Intervalls of the Strata are, either such as are there accumulated into a rude Heap, without any particular Form or Order, being only in∣cluded betwixt the two opposite Walls or Sides of the said Intervalls, which they wholly or partly fill, as there is a greater or less quantity of them; in which manner Spar is usually found here in; and other Minerals, as also the common Ores of Lead, Tin, Iron, and other Metals:

or else such as are of some observable Figure; of which sort are the Sparry Stiris, or Iceycles called Stalactite*:the Native Saline Icycles, or Sal Stalacticum: the Vitriolum Staticticum Nativum: the Vitriolum Capil∣lare: the Alumen Stalacti•um, and Ca∣pillare: Minera ferri Stalactica, which, when several of the Cylindri•k Stirlae are contiguous, and grow together in∣to one Sheaf, is called Br•sh▪Iron▪Ore: Argentum Arboresce••, & Capillare•▪ as also the Crystallized Ore• and Miner•ls, e. g. the Iron-Rhombs, the Tin Grain•▪ the M•ndick-Grains: Cryst•lli•ed Na∣tive S•lt, Alum, Vitri•l, and Sulp•••:

of which sort likewise are the Gemms or Stones that are here shot into Cubes, into Pyramidal Forms, or into angula∣ted Columns, consisting of six Sides, and mucronated or terminating in a Point: being either opake, or pellucid: or partly pellucid, and partly opake, and coloured, black, white, grey, red, purple, blue, yellow, or green: e. g. Crystall, the Pseudo-Adamantes, the Corsis-Stones, the Bristow-Stones, Cry∣stallized Sparrs▪ the Iris, the Amethyst, the Saphire, the Topaz, the Emerauld, and several others▪

My Business here is to enquire into the Origin and Production of these Metallick and Mineral Bodies: to en∣quire how they came into this condi∣tion, and attained these Figures. And as my Observations have been the light whereby I have hitherto steered my Course, so I here betake my self unto them again; and ’tis from them that I prove,

That as the more gross and massive [ 1] parts of the Terrestrial Globe: the Strata of Stone, Marble, Earth, and the rest, owe their present Frame and Order to the Deluge *: so likewise do Metalls and Minerals too; the far greater part of them, I mean all those which we now find lodged in those Strata amongst the Sand, Earth, &c. being actually reposed therein during the time that the Water covered the Earth: and the Earth it self then put into such a condition that the rest, I mean those we now find in the per∣pendicular Intervalls, should be collect∣ed thither by degrees, and be formed almost of course, meerly by the ordi∣nary Motion of the Water, and its Passage to and fro in the Earth *

[ 2] That whilst the Corpuscles of Me∣talls and Minerals▪ together with those of Stone, Marble, Cole, Chalk, and the like courser Matter: as also the Shells, Teeth, and other parts of Animals and Vegetables: were sustained in the Wa∣ter, at the Deluge †; after some time, that the violence of the Hurry and Commotion was over, and the Water come to a state somewhat more calm and sedate, such of those Corpuscles, as happened to occurr or meet together, affix’d to each other: and, many of them convening, uniting, and combi∣ning into one Mass, formed the Me∣tallick and Mineral Balls or Nodules which we now find.

Page  181That all Metallick and Mineral No∣dules whatever: as well those which are in rude Lumps, such as the com∣mon Pyritae, Flints, Agates, Onyxes, Pebles, Jaspers, Cornelions, and the like: as those which are of a more regular and observable Shape, such as the Selenites, Belemnites, Stelechites, Mi∣neral Coral: and, in one word, all others whatsoever, were formed at this time and by this means.

That in such parts of the Water where the Corpuscles so sustained chan∣ced to be all of the same kind *▪ or, at least, where there were fewer kinds or varieties of them, the Nodules, which were thus formed out of them, were more simple, pure, and homoge∣neous, as are the Selenites, and some kinds of Pebles and Flints, to name no more: But where (as indeed it ge∣nerally fell out) there happened to be a greater variety of Corpuscles, as sup∣pose of Sulphur, of Vitriol, of Alum, of Iron, of Copper, or whatever else, sustained promiscuously together, there the Nodules, formed out of them, were mixt, and consisted of a greater variety of Matter confusedly associated in∣to the same Lump. Of this the Pyrit•Page  182 may serve for an Example; whereof some yield Iron, Sulphur, and Vitriol: others Copper and Alum: yea some of them contain all these, and several more, in the same Nodule.

That the Bones, Teeth, Shells, and other like Bodies, being sustained in the Water together with these Metal∣lick and Mineral Corpuscles ‖, and the said Corpuscles meeting with, and hit∣ting upon those Bodies, they affix’d unto them, and became conjoyned with them: some of them (though this ve∣ry rarely) passing into their Pores and Interstices: others adhering in Lumps, or Masses, to their Out-sides, and in∣deed oftentimes combining in such numbers upon the exteriour Surface of the Shell, Tooth, &c. as wholly to cover and involve it in the Mass they together constituted: and others of them entering into the Cavities of the Echini, Cochleae, Conchae, and other Shells, till they had quite filled them up; those Shells, by that means, ser∣ving as Proplasmes, o• Moulds, to the Matter which so filled them, limiting and determining both the Dimensions and Figure of it.

That accordingly we at this day find some few of these fossil Shells, and other Animal Substan∣•es, with Iron-ore, Spar, Vitriol, Sul∣phur, and the like, intruded into their Pores: but far greater numbers of them with Lumps of Flint, Ores of Metalls, and Minerals, growing firmly to the Out-sides of them, and oftentimes in such quantity as that the Shell or Tooth is wholly covered by those Minerals, being immers’d or included in the Mass they constitute; insomuch that ’tis ve∣ry usual, upon breaking Flints, Pyri∣t•, &c to find Pectines, Conchae, and the like, enclosed, even in the very middle of them. As common is it to find Echini, Cochleae, Conchae, and other Shells, having their Cavities fill’d up with Ores of Metalls, Flint, Spar, Na∣tive Vitriol, Sulphur, and other Mi∣nerals. Not but that these Minerals many times survive the Shells which gave them their Forms, and are found even after they are rotted and disap∣peared; for though, when lodged in Chalk, or the like close Matter, which preserves and secures them against ex∣ternal Injuries, these Shells are con∣stantly found upon, and actually in∣vesting the Flint, Spar, or other Mi∣neral, and are commonly as fair and