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CHAPTER XIII

THE MINERALOGICAL AND OTHER CHARACTERISTICS OF GOLD, AND THE MODE OF DISTINGUISHING IT WHEN FOUND; TOGETHER WITH THE ASSAY, REDUCTION, AND REFINEMENT OF GOLD

For the purpose of presenting all that is connected with that precious metal, that has built up a state within a few years, and of making the reader fully acquainted with all that is necessary for the gold-seeker to know, we will now describe, in some detail, the natural history, character of gold, and the mode of determining its presence and value.

Gold invariably exhibits something of the peculiar yellow color which it is known to possess in a pure state; but this color is modified by various metals with which it may be mixed. Thus it may be described as having various shades of gold-yellow; occasionally approaching silver-white, occasionally resembling brass-yellow of every degree of intensity, and even verging on steel-gray in some specimens from South America.

The lustre of gold is highly metallic and shining, and owing to the small amount of oxidation at its surface, it preserves its shining lustre even after long exposure in contact with other substances. Thus the shining particles are often seen in sand when the quantity is barely sufficient to repay the cost of working, notwithstanding the value of the metal. Even however, if the surface is dull, the true color and appearance are easily restored by rubbing, and when polished it takes a very vivid lustre, which is preserved for a long time in the atmosphere.

Although in the division which has been introduced into gold-yellow, brass-yellow, and grayish-yellow, native gold seems with some slight modifications to agree with the geological relations of its varieties, yet this mode of arrangement deserves little serious notice. The gold-yellow varieties comprise the specimens of the highest gold-yellow colors, though there are some among them which have rather a pale color; they include most of the crystals and of the imitative shapes, in fact the greater part of the species itself. The brass-yellow native gold is confined to some of the regular and imitative shapes of a pale color (which is generally called brass-yellow,) and, as it is said, of a less specific gravity than the preceding one; but this does not seem to have ever been ascertained by direct experiment. The grayish-yellow native gold occurs only in those small flat grains which are mixed with the native platina, and possess a yellow color a little inclining to gray; they are said to have the greatest specific gravity of them all. The real foundation of this distribution seems to be the opinion that the first are the purest, the second mixed with a little silver, and the third with platina. It is not known whether the latter admixture really takes place, but it is certain that several varieties of gold-yellow native gold contain an admixture of silver.¹⁷

In color and lustre, inexperienced persons might mistake various substances for gold; these are chiefly iron and copper pyrites, but from them it may be readily distinguished, being softer than steel and very malleable; whereas iron pyrites is harder than steel, and copper pyrites is not malleable; for although the latter mineral yields easily to the point of a knife, it crumbles when we attempt to cut or hammer it, whereas gold may be separated in thin slices, or beaten out into thin plates by the hammer. There can thus be no possible difficulty in distinguishing these various minerals in a native state, even with nothing but an ordinary steel knife. From any other minerals, as mica, whose presence has also misled some persons, gold is easily known by very simple experiments with a pair of scales, or even by careful washing with water, for gold being much heavier than any other substance found with it (except platina and one or two extremely rare metals,) will always fall first to the bottom, if shaken in water with mud, while mica will generally be the last material to fall. This is the case, however fine or few the particles of either mineral may be.

Gold therefore can be distinguished by its relative weight or specific gravity, and by its relative hardness, from other bodies which resemble it. It is described generally as soft, completely malleable and flexible, but more accurately as softer than iron, copper or silver, but harder than tin or lead. It is useful to know facts of this kind, as a simple experiment that can be made with instruments at hand, is often more valuable than a much more accurate examination requiring materials not immediately available. Thus if it is found that a specimen (perhaps a small scale or spangle) is readily scratched by silver, copper or iron, and scratches tin and lead, it may, if of the right color and sinking rapidly in water, be fairly assumed to be gold.

The weight of gold, as of all substances, it is convenient to estimate relatively, and in comparison with the weight of an equal volume of water. The relative weight, or specific gravity, as it is called, of gold, is remarkably high, the lightest varieties being twelve times heavier than water, and pure gold nineteen times. This is expressed by saying that the specific gravity of native gold is 12-19, and the number determined by comparing the weight of the mineral in water and air.

As the value of gold depends almost entirely on its specific gravity, and this test, therefore, is of the greatest practical importance, it will not be out of place if we here explain some very simple apparatus for the determination of this point.

If the specimen then is large enough to be suspended conveniently by a thread, weigh it first in air by a fine balance, expressing the result in grains, and taking care previously to remove dust or loosely adhering particles. Then suspend it by a horsehair from the scale-pan (it is convenient to have a hook attached to it for this purpose,) and thus suspended, immerse it and re-weigh it in water, taking care that it is covered on all sides by at least half an inch of water, and carefully brushing off with a feather any bubbles of air that adhere to the surface. The results may then be noted as follows: —

This result gives the weight of a bulk of water equal to that of the specimen, and by dividing the weight of the specimen in air by this number, the specific gravity is obtained.

If, however, the substance is in the form of fine sand, or very small lumps, it is better, after weighing it carefully, to take a small dry phial furnished with a stopper; counterpoise this phial accurately in the weight-scale by shot or strips of lead, then fill it completely with pure water, taking care that no bubbles of air are left in, and weigh the quantity of water it contains: afterwards empty the bottle and dry it inside.

Next fill the bottle about two-thirds full of the powder to be examined, weigh this and record the weight. Then fill the bottle once more with water, taking care, as before, that all bubbles are expelled and none of the powder washed out. Once more weigh it.

We have then to make the following calculation:

It may be useful to know the specific gravity of various substances at all resembling gold in weight or appearance, and we therefore append the following short table. The specific gravity of water is assumed to be unity: —

By the help of this table the value¹⁸ of auriferous sand may also be in some degree estimated, since, as will be seen, the specific gravity of most of the sands is under 3, while that of the most impure gold is 12; so that if the specific gravity of the sands themselves, when experimented on, is much greater than that of ordinary sand, it is likely that the excess will be for the most part gold, in a district otherwise known to be auriferous: the greater the specific gravity, too, the greater probability there is, of this being the cause. It may also be worth while to mention here, that the specific gravity of those pepitas or lumps of gold which present a fine yellow color varies generally from 14-7/10 to 18-8/10; but when much paler they may range as low as 12-1/2, which is that of a mineral called electrum, which will be described presently, and which is a mixture of silver and gold.

When a piece of gold is broken (which is not done without difficulty – greater in proportion to its purity,) the fractured edges are very uneven and torn, exhibiting a peculiar fibrous appearance, known to mineralogists as "fine hackly." This fracture indicates that the mineral is torn asunder and not really broken, and is a proof of considerable toughness.

The form in which gold is found is various. It is sometimes crystalline, in eight or twelve-sided regular figures, passing into cubes, but the crystals are generally small and rare. In case of such crystals being found, it is well worth knowing that they possess a value as mineral specimens far beyond that of the gold which they contain.

More frequently the metal is found in lumps or grains, called by the Spaniards pepitas, varying in size from that of a pin's head to masses weighing, as has been already mentioned, nearly one hundred pounds troy. The term pepita is only applied to grains of some magnitude, and the most common limits of size are from that of a small pin's head to that of a nut or gooseberry.

When much smaller and still rounded, they are called gold dust, and when flattened, scales or spangles. In nature, and when seen in veins of quartz, gold often occurs foliated, or in leafy expansions of extreme thinness, or in branchy (dendritic) forms, probably made up of minute crystals. It is in the form of very minute grains that the metal is generally disseminated through rocks and auriferous ores of various metals, and these are reduced according to circumstances in methods that will be alluded to in a future chapter. In pepitas and small grains it is carried down by streams and deposited in their beds, the pepitas being usually most abundant where there is reason to suppose considerable disintegration of the surface, and where the action of denuding causes to a great extent is evident. The coast of Africa and the rivers of Europe are examples of the former case, while the Siberian deposits and those of California would appear to belong to the latter.

The following are examples of the constituent parts of various specimens of gold obtained from different gold districts, and will form a useful guide for comparison.

Table showing the Composition of Native Gold. ¹⁹

The gold from California, according to the assay of Mr. Warwick of New York, yields 89·58 per cent, pure gold, and is therefore, about equal to that obtained from the washings of Miask (the richest district in Western Siberia, and that producing the largest pepitas,) and superior, as the assayer remarks, to the gold dust from Senegal.

There is a remarkable mixture of native gold with silver occasionally found in Siberia, and known under the name of electrum. Its color is pale brass-yellow, passing into silver-white. It occurs in small plates and imperfect cubes, and possesses many of the characters of gold, but it consists only of 64 per cent. of that metal, and 36 per cent. silver. It is at once known by its low specific gravity, which does not exceed 12.

Other mixtures of gold are (1) a rhodium-gold found in Mexico, and containing 34 to 43 per cent. of rhodium, having a specific gravity of 15½ – 16·8, and a clear, dirty yellow color; and (2) a palladium-gold (containing 9·85 per cent. palladium, and 4·17 per cent. silver) found in Brazil and elsewhere in South America, in small crystalline grains of pale yellow color. The auriferous ores of tellurium, including silver, have hitherto only been found in Transylvania. Their color is steel-gray, and they tarnish on exposure. The variety called graphic-gold, or graphic tellurium, consists of about 60 per cent. of tellurium, 30 per cent. gold, and 10 per cent. silver, and is worked chiefly as an ore of gold. Another variety, "yellow gold glance," yields somewhat less tellurium, gold and silver, and as much as 20 per cent. of lead.

Having now explained at some length the more manifest characteristics of gold, namely, its color, hardness, and specific gravity, it is necessary, before explaining the mode of separating it from associated minerals, that we should here give some account of the behavior of this metal under the blowpipe, and when exposed to simple chemical tests. The assay of gold and its accurate analysis, we postpone for the present.

The method of blowpipe analysis, although exceedingly useful, is not absolutely necessary in the case of gold, because of the many readier ways of determining the metal, but it seems advisable to state the appearances presented. All the varieties are readily fusible into a globule, which when the gold is pure, is unaltered by the continuance of the heat. In this respect it differs entirely from iron and copper pyrites, which, on being exposed to the flame, give off sulphur fumes and undergo considerable change. In the case of gold containing other metals, these, with the exception of silver; may generally be got rid of by continuing the heat in the exterior flame with the addition of a little nitre. Before the oxy-hydrogen blowpipe, the metal is volatilized in the form of a purple oxide.

Gold is not acted on by any of the acids alone. When exposed to the mixture of nitric with hydrochloric acid (in the proportion of one part nitric to four of hydrochloric) called aqua regia, it dissolves without residue, the solution giving a purple precipitate with protochloride of tin, and a brown precipitate with protosulphate of iron. Electrum, the mixture of silver with gold above alluded to, is only partially soluble in aqua regia, giving a residue of chloride of silver. The solution is acted on by protosulphate of iron, as already explained.

The following simple mode of detecting attempts at imposition in gold dust is worthy of being recorded in this place.

Place a little gold dust in a glass tube or earthenware saucer, and pour nitric acid upon it; then hold the glass or saucer over a flame, or upon a few embers, until red flames (nitric vapors) arise; if it be pure gold, the liquid will not become discolored; but if pyrites or brass-filings should have been mixed with it, the acid will become turbid, green, and black, discharging bubbles of gas. After the ebullition has ceased, the residue should be washed with water, and acid again poured upon it, when the same effect may be observed, but in a less degree; and if the experiment be repeated till all effervescence ceases, it will finally leave the gold dust pure.

CHAPTER XIV

ADDITIONAL RECENT EVENTS

The history of the laws of a State affords the best idea of its social condition – present and prospective; for they are framed from the necessity of circumstances and the demands of the inhabitants. We may, therefore, see the condition and the progress of the Californians in their legislative transactions.

The California Legislature adjourned on the 22d April. They have passed a law creating a State assayer, until a mint be established in California. Among the one hundred and forty-three acts and joint resolutions passed, we notice the following:

To incorporate the cities of Benecia, San Diego, San Jose, Los Angeles, San Francisco, Sonoma, and Santa Barbara, and a general act for the incorporation of cities; concerning the State revenue, etc., and its management; creating loans temporarily, appropriations, and other fiscal acts; relating to the appointment of pilots, regulating the duties of harbor masters, declaring certain rivers, etc., navigable, creating health officers for San Francisco, creating a marine hospital, regulating quarantine at San Francisco, providing for the inspection of steamboats; subdividing the State into counties, establishing county seats and providing for the complete organization of all the counties; organizing the supreme court, providing for the early publication of the laws, organizing district courts throughout the State, establishing a municipal court in San Francisco, abolishing all laws in force in the State, except such as were passed by this Legislature, adopting the common law, regulating the interest of money, public ferries, notaries public, jails and jailers, limited partnerships, roads and highways, public elections, volunteer companies, wills, militia, liens of mechanics and others, descents and distributions, bills of exchange and promissory notes, constables, coroners, guardians, fraudulent conveyances and contracts, the rights of husband and wife, incorporation of colleges, marriages, auctioneers, government and protection of the Indians, settlement of the estates of deceased persons, proceedings against debtor by attachment; creating the office of State assayer, melter and refiner of gold, to regulate Senatorial and Assembly districts, prescribing the mode of maintaining and defending possessory actions on lands belonging to the United States; to prevent the importation of convicts; for the better regulation of the mines and the government of foreign miners, the national Washington monument, pay of chaplain, the Pacific railway, and concerning grants of land by the General Government to commissioned officers who served in the late war with Mexico.

Here we have all the machinery necessary for the full regulation of a large, commercial, agricultural, manufacturing, and mining community. The session of the Legislature must have been laborious, indeed; but the members have acquitted themselves of their arduous duties rapidly and well. One great measure adapted by the Legislature was the substitution of the common law for the uncertain civil law which existed in California when ceded to the United States. The whole legal administration will now conform to that of most of the other States of the Union. The provisions in the Constitution for the purpose of education, have been nobly carried out by an act for the incorporation of colleges.

Agriculture in California appears to be improving, and as it is getting to be as profitable as any thing else, it is attracting increased attention. Boxes of garden seeds which had cost nine dollars, have been sold for one hundred dollars, and scythes which cost three dollars, sold for forty-five dollars. The seeds which were sent around Cape Horn, were almost useless, while those which went over the Isthmus, hermetically sealed, came up first. One man near San Jose, has made fifty thousand dollars by raising potatoes. What toil in digging and washing gold would be necessary to realize that amount!

Among the recent mining incidents, the following is remarkable: – Last winter, three men accidentally struck upon a rich deposit of gold, in a gulch about twelve miles from Knight's Ferry, on the Stanislaus River, and four or five miles back from it. They worked this vein with great success, managing to keep it a secret, until an Indian, wandering through the locality, discovered the secret, and communicated it to his tribe. The next day, several hundred Indians fell to work, with the same success; but as they spent their earnings in gambling and drinking at night, they incautiously let out the secret, and it spread among the whites. The latter, without scruple, took possession of the ground, and set the Indians adrift. An alcalde was elected, the ground staked off, and allotted to the several claimants. This gulch, although rifled of its richest treasures, afforded good digging for a large number of persons, for some weeks, many carrying away, when the water failed, a thousand dollars and upwards, as the result of their labors. The three discoverers of the gulch, took away with them about forty pounds of gold to each man, all scraped up in the short space of seven weeks.

Imitation lumps of gold have been made and brought into circulation in California. The State Assayer states that above forty specimens have been brought to his notice. They are generally in size from four to five ounces to a pound in weight – quartz, and every thing else necessary to make them look right, properly intermixed.

It has been definitely settled that gold does exist in the vicinity of San José. Specimens have been taken to San Francisco.

Several artesian wells have been constructed at San Francisco, since the second great fire, and it is thought that others will soon add to the comfort and convenience of the people of that city. The want of good water for drinking purposes, has been the most serious objection to San Francisco as a place of residence; and additional incentive to exertion in the matter is furnished by the constant apprehension of destructive fires.²⁰

Coal has been discovered in California, in various places, and is reported to abound in considerable quantities in the neighborhood of San Francisco. Every day developes some new wealth of this land of treasure, and we regard the discovery of the abundance of coal as in the highest degree important to the residents of California. Even amid the news of the extraordinary yield of the gold region during the present year, 1850, when a single vessel, in one trip, brings $2,000,000 worth of gold dust to the United States we can pause to notice the discovery of the more useful substances.

The Trinity River and Humboldt Harbor, in the north-western part of California, have lately become a resort for the superfluous population of the Sacramento and San Joaquin regions. The harbor is pronounced a very good one, and the discovery of abundance of gold on the branches of Trinity River, will, doubtless, contribute to the building of a large town upon its shores.

In the middle of June, there was much excitement in San Francisco, caused by the reported discovery of a gold lake, among the mountains between the South Fork of Feather River and the Yuba. One man was said to have got $7000 in four days, and a party of ten Kanakas were reported to have got $75,000 in a week. A vast number of people were by this means attracted to the sources of the Feather and Yuba Rivers, and though they found the lake story a hoax of a vile character, they found tolerably fair diggings, which would console them for their disappointment.

The following extract from the Placer Times of the 17th of July, 1850, under the head of "Great Discoveries of Gold – Gold Lake," will afford the reader a lively conception of the degree of excitement caused in California by every new announcement of a newly discovered locality abounding in gold:

"We were inclined to give only an average degree of credit to stories that have reached us during the past few days, of the unprecedented richness which this locality has developed. A few moments passed in Marysville on Saturday, convinced us that there is much more show of reality in this last eureka report, than usually attaches to the like. In a year's experience of local excitements from the same cause, we have seen none equal to what now prevails in that town. It has visited all the inhabitants indiscriminately, lawyers, doctors and judges, traders, teamsters, mechanics and gamblers. Our readers know we are the last to justify the circulation of unfounded or exaggerated reports, but we deem it right to conceal nothing of what may prove (for aught that we can see to the contrary) one of the most astounding discoveries in the modern history of diggings. The specimens brought into Marysville are of a value from $1600 down. Ten ounces is reported as no unusual yield to a panfull, and the first party of sixty, which started out under the guidance of one who had returned successful, were assured that they would not get less than $500 each per day. We were told that the previous morning two hundred had left the town with a full supply of provisions and four hundred mules. Those who could not go were hiring others in their stead. The length of the journey and the quantity of provisions required, there being no stores in the region, rendered an outfit rather expensive. Mules and horses had doubled in value, and $400 were considered no more than enough to furnish a proper start.

The distance to Gold Lake was first reported two hundred miles; the best informed, however, say that it is but little more than half of that. It lies at a very considerable elevation among the mountains that divide the waters of the South Fork of Feather from those of the north branch of the Yuba. The direction from Marysville is a little north of east. The story has of course spread ere this far and wide among the miners high up on the Feather and Yuba, and the spot will be as crowded as all other good places are, ere the tardy adventurer from this region could reach it. The region of the Gold Lake wonders is a new one, however, and lies between what are established to be diggings of unsurpassed richness. It is our belief that it is better for one who has got some initiation into the gold mysteries, (if there be any,) not to be content in old 'used up' localities, but to push along to the great field yet unexplored; and that, though the search be long and laborious, the big lift is ultimately pretty sure for those who are patient and persevering."

The same paper of July 18th, contains additional particulars, having a tendency to add plausibility to the reports. Among other things, a man by the name of McLelland came into Marysville on the 17th, with $7000, the result of four days' labor at Gold Lake. Whatever may be the truth of the reports, there is no doubt of one thing – the whole population of Marysville and its vicinity have become infected by the news, and are taking up their march thitherwards in crowds.

The Transcript speaks rather doubtingly on the subject; it says – "The reports come as a general thing, through teamsters and other persons whose interest it is to give as favorable accounts as possible. The statements are very conflicting."

To this we may add the statement of a gentleman who reached this city from Marysville, direct, on Tuesday night. The excitement, he says, is great; but no one could give any definite information of the locality or of its productiveness. Yet all seemed to think there was no doubt in the matter, and as many as could get away were starting, or getting ready to push for the new El Dorado. Upon his way down, on board the boat, he conversed with a man who professed to have explored that region lately, although he did not claim to know where Gold Lake was. But between the North Fork of the Yuba and Feather Rivers, at the foot of the great chain of mountains, he reported a series of lakes of various dimensions, and "two thousand people," prospecting all about. The snow was very deep – "six feet" – and but little gold.

The following extract from the Placer Times, is the most positive information within our knowledge.

On the arrival of the "Lawrence," yesterday, from Marysville, we received more news of the Gold Lake excitement, now prevailing in those parts. It promises to spare no one. Many who would not be understood to have yielded to it, seek, under various pretences, to get away – some pleading business in other quarters of the mines; others desiring the recreation of a country jaunt. It is reported that, up to Thursday last, two thousand persons had taken up their journey; that many who were working good claims, and had made considerable progress, were deserting them for the new discovery. Mules and horses were almost impossible to be obtained. A supply from this quarter was expected daily, and most anxiously awaited. Although the truth of the report rest on the authority of but two or three who have returned from Gold Lake, yet but few are found who doubt their marvellous revelations. The first man who came into Marysville took out a party of forty as guide, on condition they paid him one hundred dollars each if his story was verified, and offering his life as a forfeit for any deception.

"This party, it is understood, came near losing their way, from the difficulty the guide found in retracing his path, after the snow had melted. Fortunately, however, they encountered another man, who was on his way returning, and he showed the track. The second person has since left with a much larger party, who are to give him two hundred dollars each, and the same forfeit is provided. The spot is described as very difficult of approach, and it is feared that many will lose their way. A party of ten Kanakas are reported to have wintered at Gold Lake, subsisting chiefly on the flesh of their animals. They are said to have taken out about $75,000 the first week. The lake is not large, and, after the wet season ceases, has no outlet; at present, however, the water runs over the basin, and finds its way into the North Fork of Feather River. At a lower stage, it admits of easy drainage, and the undertaking is already projected.

"Of course the most extravagant anticipations are founded on the result of this work, induced by the yield from the borders of the lake which have already been realized. The "placer" proper is very limited, and little encouragement is given as to the character of the surrounding country; indeed, it is probably entirely unexplored, as the region lies about as far up among the snows as the most adventurous have yet penetrated."

The Yuba River is destined to be thoroughly rifled of its wealth. Three miles above the new town of Lina, a company has turned the river from its course, and made it run through a lateral slough. Prospecting of the bed has proved very satisfactory, and the shares in the company's stock have sold at a high rate.

As was apprehended, various difficulties have occurred between the owners of land at Sacramento City, and a large number of squatters upon it. The ground was bought and surveyed, and the title to ownership was perfect. But the number of emigrants who arrive at Sacramento at particular seasons forces them to encamp outside of the regularly built town, and when thus encamped, they consider themselves as settlers, and are unwilling to give up possession of the ground. The power of the law has been called into requisition several times to eject these squatters.