Gold Milling Technology and Methods: Phase One, 1861-72.

Once the ore had been hoisted from the mine, it had to be sorted and crushed before it was milled to recover the gold. Tramways were built by some companies to transport the ore from the shafts to the mill buildings, but most often it was hauled by wheelbarrow or horse and cart.⁽¹⁾ Mills were not always located close to the mine. The availability of cheap labour was one factor that permitted mill owners and mining entrepreneurs to build where they pleased.⁽²⁾ In Goldenville two steam mills were built on the St. Mary's River near the wharf; both the Wentworth Mill and the Canada Mill were built in 1868. Two water mills the Oulton Crusher and the McDonald Crusher were located on water systems beyond the diggings.⁽³⁾ (ILLUS. 8)

According to T. Sperry Hunt's 1868 report for the Geological Survey of Canada (GSC), the mineral was taken directly to the mill to be sorted, "the barren portions rejected and the material reduced to fragments of proper size."⁽⁴⁾

It is likely, however, in the less capital - intensive operations that the quartz may have been crushed closer to the shafts. An 1869 map of the property of Messers. Tucker, Tobin and Canning at Oldham shows a quartz house close to three shafts, approximately 1800 feet from the crusher.⁽⁵⁾ (ILLUS. 9) The small independent operations would have crushed their own quartz before transporting the pieces for crushing at the local custom mill.⁽⁶⁾ To maximize the efficiency of the stamp mill, the 'ideal' reduced size for the quartz ore was a two-inch piece.

In the earliest phase of mining, the quartz was broken into smaller pieces with sledge hammers.⁽⁷⁾ Crushers were employed by few of the larger operations such as the New York and Nova Scotia Gold Company at Tangier, circa 1864. The quartz was pulverized in the stamp mill but was "first cracked by a machine which resembled a Blake's Stone Breaker".⁽⁸⁾

"A multitude of crushers have been tried to break up the quartz before it is given to the stamps or other pulverizing apparatus, but the number in use is very small. Those principally in use consist of two heavy iron jaws, which are wide apart at the top and close together at the bottom, and as they work back and forth, the quartz is smashed between them. The quartz is usually in pieces not larger than goose eggs when delivered to the battery"…⁽⁹⁾

By the end of the decade mining authorities were recommending the implementation of stone breaking devices to reduce the amount of manpower and increase the efficiency of the mining operation.⁽¹⁰⁾

Once the quartz had been reduced to two-inch pieces or less, it was ready to be pulverized in the stamp mill. The stamp mill was used to facilitate two processes in the recovery of gold from quartz - pulverization and amalgamation. The design of the apparatus evolved from the 14^th-century gunpowder mill and the 19^th century Cornish tin mine stamp mill.⁽¹¹⁾ (ILLUS. 10, 11, & 12)

Two types of mill were employed in the Nova Scotian gold fields: the Chilean mill and the Californian stamp mill, the latter having evolved from the former. The Chilean mill, used in Waverley in the early 1860s, was found to be a less efficient device for recovering small amount of gold from large portions of quartz.⁽¹²⁾ The Californian stamp mill was far more popular choice amongst the miners and entrepreneurs⁽¹³⁾

The anticipation of instant wealth, as well as the realization that a mill building improver the value of the gold property, was reflected in the numbers of mills that were constructed throughout the gold districts. By the end of 1862 there were thirty crushing mills; ten years later the had grown to fifty-two, although no more than a dozen were in operation.⁽¹⁴⁾

There are few descriptions of the buildings that were constructed to house the stamp mills or crushing machines erected throughout the Nova Scotia gold district at this time. One is that of the Alpha Company mill in the Mount Unicake District. The eight-stamp mill constructed c. 1868 was housed in a pine building that also contained sleeping quarters for the superintendent and his men. No physical dimensions of the building were provided in the properties.⁽¹⁵⁾ The mill building erected by the New York and Nova Scotia Gold Company at Tangier was housed in a farm building measuring 40 x 50 feet, and was two stories in height. A boiler was annexed to the structure to house the two cylindrical boilers, each 28 feet long and 42 inches in diameter, which supplied steam to the steam engine.⁽¹⁶⁾

ILLUS. 2 and 3, of Goldenville, 1869, show a number of barn-like structure with substantial chimneys constructed of what appears to be bricks. Most of the mills within Goldenville were operated by steam engines, necessitating such a structure. The mills appear to be little more than wooden barn-like structure, with pitched roofs. It is difficult to determine the number of stories, the placement of windows or doors within these structures. Since no tramways appear in either photograph, the ore must have been transported to the mills by means of horse and cart or wheelbarrow. For the former, a substantial door must have been available.

The safest assumption that one could make about the mill buildings constructed during this period would be that they were crude, wooden structures which were not expected to last. The stamp mills were portable to some extent, and it was not uncommon for them to dismantled and removed to another site.

Following is a list of Goldenville mill owners and their mills from 1862 until 1873:⁽¹⁷⁾

This early period of activity corresponded to the development and increases use of steam power in the province's manufactories.⁽¹⁸⁾ In Sherbrooke the majority of the stamp mills in use between 1862 and 1872 were steam powered, even though this form of power was more expensive.⁽¹⁹⁾

The engine used in the steam stamp mills ranged between 10 and 15 horsepower. The 16-stamp Wellington Mill in Goldenville was operated by a 15 horsepower steam engine and was capable of crushing from 16 to 20 of quartz per 24-hour period. The Palmerston's 10-stamp mill could crush 10 tons per 24-hour period with its 10 horsepower steam engine.²⁰⁾

As mentioned, the mill most commonly employed in the Nova Scotian gold fields was the Californian stamp mill. Although mills were imported from the United States, ⁽²¹⁾ it was not long before local foundries begin to advertise "quartz crushers on the most improved plan" in the province's newspapers and directories. Among the foundries producing gold mining mills and equipment were W. H. Davis in Pictou; the New Glasgow Iron Foundry owned by W. and J. W. Fraser; Isaac Matheson and Company, New Glasgow; Sibley, Caffrey and Company, Truro; Thomas Mitchell, Halifax; Henry Dimock and Company, Windsor.⁽²²⁾ (ILLUS. 13 & 14)

Following is a description of the type of mill that had evolved by the late 1870s:⁽²³⁾

[ILLUS. 15] represents the ordinary Californian pattern of stamp mill. The stamp is a cylindrical iron pestle faced with a chilled cast iron shoe, removable so that it can be renewed when necessary, attached to a round iron rod or lifter, the whole weighing from 600 to 800 pounds. The life is effected by cams acting on the under service of tappets a, and formed by cylindrical boxes keyed on to the stems of the lifer about one-fourth of their length from the top. The bed or mortar A is cast-iron. The height of the lift may between 8 and 10 inches, and the number of blows from 30 to 90 per minute.

The early mills in the province did not match the above prototype exactly. At first, the mortar boxes were constructed of wood with heavy plate of iron fitted into the base. The stamps were often cast iron, although there was a gradual move toward the use of steel shoes and dies.⁽²⁴⁾ The Material used in the stamp stem also changed during that period from wood to wrought iron. One contemporary writer argued that the best mills had iron rather than wooden lifters.⁽²⁵⁾

Another variation in the Nova Scotian mills was the arrangement of stamps in each battery. In the Californian mill there were generally five stamps per battery, while here there were a number of mills employing an arrangement of four stamps.⁽²⁶⁾

Ophir Mining Company, Renfrew (1864)
16 stamps;

Wellington Mining Company, Goldenville (1868)
4 batteries of 4 stamps each;

Palmerston Company Mill, Goldenville
Single battery of 4 stamps, and
2 united of 3 stamps each;

New York and Sherbrooke Mining Company, Goldenville (1864)
8 stamps

Hayden and Derby Mining Company Mill, Goldenville (1868)
15 stamps.

Toward the end of the decade many mills were using the five stamp arrangement.⁽²⁷⁾

There was also variation form mill to mill in the weight of stamps employed, as well as their height and rate of drop. Stamps weighed from 525 pounds and the height of drop varied from ten to fifteen inches. The rate of strokes per minute per stamp was from 50 to 75. These variations reflected the variety ploiting the stamp mill.⁽²⁸⁾ The function of the mill to pulverize the quartz was agreed upon; however, there would appear to have been a divergence of opinion about the amalgamating capacity, and the best way to exploit it.

Another modification in the mills in the province was the shape of stamps used:⁽²⁹⁾

There are two systems of stamps in use in Nova Scotia - those with square heads and those with round and rotating heads …

This variation was reflection of the origins of the contractor (or owner) of the mill facility. The mills were erected by either American or British concerns, each of which had their own preferences. The American system was designed so that the can not noly lifted the stamp stem but rotated it slightly on its axis. In the English system, evolved form Australian gold fields, stamps were square and non-revolving. Gradually the American design predominated throughout the province.⁽³⁰⁾ (ILLUS. 16)

The crushed quartz was fed into the battery and then, during the stamping operation,

A quantity of water sufficient to aid the pulverization and amalgamation, and to carry out the pulverized mineral, is supplied to each stamp by means of tubes furnished with stop-cocks. In front of each battery is a rectangular opening which is closed by means of a frame or movable sash, covered with a fine screen or grating, the liquid mud formed by the pulverization of the mineral under water, and projected from the boxes by blows of the stamps, passes out and flows out over a series of fixed or oscillating tables, slightly inclined, and placed one below the other, at different levels, before being covered as waste or refuse to a place of deposit without. The metallic gratings in front of the batteries have generally from 160 to 200 holes to the square inch. The finer the grating the less the amount of material stamped in a given time, but the more complete the treatment.⁽³¹⁾

The addition of water to the battery facilitated the pulverization as well as the amalgamation, However, in these early mills, the water was added above the dies at the top of the mortar box. (ILLUS. 15). Adding it as this level caused the spaces between the dies to become fully packed with the crushed material and thus hindered the >complete operation of the battery system. In addition, the arrangement of four stamps per battery, rather than the three or five stamp system, did not assist the movement of the crushed quartz throughout the battery. As a result the stamp mills were not operated at their potential level.⁽³²⁾

The failure to fully exploit the capacity of the mill was consequence of the poor level of metallurgical skills and interests of the mining concerns in the province.⁽³³⁾ Although most operators would agree that the mill was means of thoroughly reducing the quartz, few appeared to understand how it could best be used to facilitate amalgamation. This was reflected in the debates about the degree of fineness to which the quartz should be placed at the battery opening, the use of mercury in the battery, and addition of water. Opinions varied about these issues and various practices resulted.

In many mills the grating, which supported the metallic screen at the face of the battery was fixed in a vertical position, although "a slight inclination outwards, to favour the escape of the pulverized matter…" was to be referred.⁽³⁴⁾ The angle not only assisted the movement of the mud out of the battery, it also reduced the wear of the screen by causing the particles of ore to be forced from under the stamp at a smaller angle.⁽³⁵⁾

Related to the angle of the gratings was the degree of fineness to which the ore ought to be pulverized.

The finer the grating, the less the amount of material stamped at a given time, but the more complete the treatment. I am inclined to believe that many of the mill workers, not taking into account the smallness of the particles of gold, do not pulverize to a sufficient degree of fineness.⁽³⁶⁾

However, another 1860s writer argue that if the ore was crushed too fine, the finer particles were more likely to be carried away with the water and to escape amalgamation altogether.⁽³⁷⁾ Writers later in the century argued that the quality of the ore determined the degree to which it should be pulverized:

An ore, the main richness of which lies in its sulphurets, should be crushed comparatively course, so as to avoid reducing the valuable sulphurets to slimes, which are difficult to save and threat subsequently. If the sulphurets are finely disseminated, the ore must be crushed more finely than when they are in coarser crystals, so as to facilitate their separation from the worthless gangue, the object being to produce a minimum of particles that can consist partly of sulphurets and partly of quartz; obviously the minimum size of the crushed particles must therefore be somewhat less than that of the valuable particles in the original ore.⁽³⁸⁾

Mercury was added to the battery at regular intervals to facilitate the amalgamation process, although from the writings of Hunt, Stillman and others it would appear that this was not a universal practice.⁽³⁹⁾ However, by the middle of the decade the addition of mercury to the stamp battery had become a regular part of the mill man's job. At the Ophir Gold Mine in Renfrew, a spoonful of mercury was added to the battery at the beginning of the operation and then every four hours later. Then, after a few days of working and depending upon the quality of the mineral, the quantity of mercury was increased or decreased.⁽⁴⁰⁾

A problem encountered by millmen in the amalgamation process was "the sickening" or "flouring" or mercury - "that is, the particles, losing their bright metallic surfaces, are no longer capable of coalescing with or taking up other minerals."⁽⁴¹⁾ Independently, an American and an Englishman discovered that the addition of a small quantity of sodium to the mercury would solve this problem. In March, 1886, Dr. George Lawson read a paper before the Nova Scotia Institute of Science outlining the use of sodium amalgam in recovering gold from ore high on arsenic pyrites. In September of that year, Lawson and Dr. Krackowizer, manager of the Lake Major Company Gold Mines ("the crusher and other machinery of these mines being much superior to those of any similar establishment in the province") experimented with the addition of the sodium amalgam. Dr. Lawson reported that the experiment on the tailings at the mines gave returns of the rate of five ounces per ton of pyrites.⁽⁴²⁾ In his report T. S. Hunt noted that sodium amalgam had been adopted to some extent in the provincial mines, but "has probably not yet received the thorough trial which it merits". Among the companies regularly employing it was the Wellington Mine in Goldenville.⁽⁴³⁾

Much of the gold within Nova Scotia was coarse and "free milling" and could be Recovered in the batteries with the addition of mercury.⁽⁴⁴⁾ A further amount was recovered through the use of copper amalgam plates arranged at the front of the screen by the combination of the stamping action and the water force. The arrangement of tables varied from mill to mill. At the Ophir Mill in Renfrew, the following system was used:⁽⁴⁵⁾

The liquid mud from the pulverization, passing from the battery through the grating, flows over four fixed tables, placed one below the other. The first, or uppermost table is the shortest, and is trapezoidal in form; the dimensions of the two parallel sides being three and a half and two and a half feet. The three succeeding tables are rectangular, and have espectively the length of seven, eight and six feet; their breadths being twenty-four, fourteen and twelve inches.

In other mills, tables were rectangular or designed in the form of sluices or equipped with a series of riffles or transverse grooves containing mercury. Some mills had fixed or shaking tables that moved with either a lateral or back and forwards motion.⁽⁴⁶⁾ The tables at the Wellington Mine, "one of the best in the region", were fixed and designed in the form of sluices.⁽⁴⁷⁾ Both the New York and Sherbrooke and the Hayden and Derby mills in Goldenville were equipped with shaking tables.⁽⁴⁸⁾

Almost from the beginning of this period of mining there was concern expressed about the amount of gold that escaped battery amalgamation and flowed out of the mill with quartz tailings.⁽⁴⁹⁾ Although much of the gold in the province was free milling, it was "also intimately bound up with sulphides requiring other methods of treatment for recovery".⁽⁵⁰⁾ Professor George Lawson argued that the use of mercury alone was quite inefficient "owing to the presence of sulphides" which coated the gold and prevented the action of the mercury upon it.⁽⁵¹⁾

There were attempts in some mining operations to overcome these problems. One early method was the roasting of the quartz prior to pulverization. The New York and Nova Scotia Gold Company at Tangier built kilns in which to roast the quartz in order to drive off the arsenic and sulphides bound up with the quartz and gold. Sillman questioned the wisdom of this approach on account of its additional cost as well as the tendency of the quartz to become "friable" and more difficult to treat. In addition there was a problem in retrieving the gold from the pyrites after calcinations.⁽⁵²⁾ This practice appears to have been abandoned by 1868.

The same New York and Nova Scotia Gold Mining Company installed a system of buddles "to concentrate the pyrites" in the mid 1860s, and there were attempts in the Sherbrooke Gold District to treat the tailings.⁽⁵³⁾ Many of the tributers who took over abandoned mining properties in 1872, following the collapse of the industry, worked the tailing dumps to recover whatever gold remained behind. Ira Twist continued to work the Palmerston mine and in 1873 installed a buddle and three tables, measuring eight feet by two feet wide covered with copper amalgam plates, each of which was terminated by a riffle. The tailings were mixed with water and passed through a revolving screen of one-eight inch mesh. The finer tailings were then passed over the tables; small jets of water were used to keep the tailings moving along the surface of the plates. By means of this system Twist was reported to have recovered 41 ounces of gold from 675 tons of tailings.⁽⁵⁴⁾

However, by and large, systems were not installed during this early period to recover the gold that escaped battery amalgamation.⁽⁵⁵⁾

At regular intervals the mill was shut down to allow the amalgam to be removed from the batteries and copper-plated tables; as known as cleaning up the mill. The frequency with which the mill was leaned-up depended directly upon the richness of the mineral.⁽⁵⁶⁾ Hunt noted that the Ophir mill batteries were cleaned once every two weeks, while the tables were cleaned once in three or four days, or even daily if the mineral was that rich. Following is Hunt's description of the process in one mill at Uniacke Mines:⁽⁵⁷⁾

This process… is effected by a stream of water from a hose, which removes the sands from the tables and allows the amalgam to gathered up from the plates. For the batteries, the stamps being raised, and the grating removed, a jet of water is employed to break up the compacted mass of partially stamped mineral, which fills the box; the larger fragments being removed by hand, until the amalgam accumulates at the bottom. The dies are then cleaned and taken up, and the washed amalgam gathered into a mass, and added to that already obtained from the tables. The excess of mercury is then removed From this pressing it in a chamois Leather, or in a closely-woven wet cloth; balls of proper size and heated in a cast iron retort, which is previously lined with a paste of clay and water, to prevent the adhesion of the gold. The portion of mercury which still remains with the gold being expelled by heat, its vapours are carried over and condensed in water, and at the "end of the operation the gold remains in the retort in the form of spongy masses, which are melted in a crucible, and cast into ingots." (ILLUS. 17)

1.

¹ B. Silliman, Jr. Report on the Gold Property of the New York and Nova Scotia Gold Mining Company, with an Introduction to the General Structure and Geology of Nova Scotia Gold Fields, (New York: George F. Nesbitt 1864), p.30. This company, located at Tangier, constructed a tramway to haul the ore from the hoisting shaft to the mill building.

2.

² A. Gilman, op. cit., p.583: The price of labour "rarely rises above a moderate $.90 per day." (1864). In Wine Harbour wages were 5 shillings per week in 1862, and the cost of conveying the material to and from the mines was cheap. In 1886 the rates at Goldenville were reported to be $1.00 per 10 hour day. AJM, v.l, n.19 August 4, 1866. A.R.C. Selwyn, "Notes and Observations on the Gold Fields of Quebec and Nova Scotia", Geological Survey of Canada, Progress Report, 1870-71, (Ottawa: Queen's Printer, 1872), p.281. The price of labour in Nova Scotia was estimated to be between $1.25 and $1.50 per day. In 1873, the closure of mining properties and increase of the tribute system was attributed to the rising cost of labour. N.S. RMD, 1873. See also N.S. JHA, 1875, Appendix 4, Mines Report. Mills were also built to inflate the value of the mining property, thus location of the building was not always a primary consideration. See S.P. Hunt, op. cit., p.k2; W. Malcolm, op. cit., p6.

3.

³ The map "Sherbrooke Gold District" (PAC H2/219, ILLUS. 8, following

page in this report) shows the Wentworth and Kingston and Sherbrooke Stamp Mills as being located on either side of the main Goldenville wharf. "General Plan of the Sherbrooke Gold District ", in H.Y. Hind, Report on the Sherbrooke Gold District (1870), General Plan depicts the Wentworth and the Canada Mill in the failure of some mining companies to the tendency to locate mills without reference to the mine workings or the general landscape of the area. The Wentworth Company was sold at a sheriff's sale in December 1869 (AJM, v.IX, n.8, Feb. ww, 1870); neither the Canada Company nor the Kingston and Sherbrooke Company worked for any length of time in Goldenville. W. Malclom, op. cit., p.228. All the above mils were steam powered, rather than water powered, so they did not have to be located on the river.

4.

⁴ T. S. Hunt, op. cit., p.14.

5.

⁵ Shelford and Robinson, Report on the Property of Messrs. Tucker, Tobin and Canning at Oldham, N. S. (London: Waterlow and Sons, 1869).

6.

⁶ Anonymous, The Gold Seeker's Guide …, p. 14"… the greater part of the gold obtained [at Tangier] has been extracted from the quartz by merely breaking it up with hammers, the fragments remaining on hand, to be afterwards ground in a quartz-mill…"

7.

⁷ A. Heatherington, A Practical Guide …, p.111.

8.

⁸ B. Silliman, op. cit., p.20 - 21.

9.

⁹ A. Heatherington, A Practical Guide …, p.111.

10.

¹⁰ H. Y. Hind, Report on the Waverley Gold District, (Halifax: Annand,

1869) p. 54.

11.

¹¹ The 19^th century gold stamp mill dates back to the 14^th century and the production of gunpowder. It was not until the 15^th and 16^th centuries that such a device was used to crush gold ores. ILLUS. 10 is a drawing of "ancient mill"; ILLUS. 11 is Diderot's conception of the stamp mill used to recover gold from ore. The Cornish stamp mill, ILLUS. 12, was used in the 19^th century tin mines and perhaps bears the closest resemblance to the mill employed in the Californian gold fields after 1849. Sources: Algernon Del Mar, Stamp Milling: A Treatise of Practical Stamp Milling and Stamp Mill Construction, (London: McGraw-Hill Book Co., 1912) p. 2 - 4; A. Diderot, Pictorial Encyclopedia of Trades and Industry, (New York: Dover, 1959, Paris, 1763.) Plate 137.

12.

¹² S. P. Hunt, op. cit., p. 13 - 14; B. Silliman, op. cit., p. 20 - 21.

13.

¹³ Encyclopedia Britannica, (9^th edition Edinburgh: Adam & Charles Black, MDCCCLXXIX), vol. X, "Gold", p. 746 -47. The Californian stamp mill was considered "the best method thus far developed in actual practice on a large scale for the treatment of auriferous quartz". Engineering and Mining Journal, (formerly the American Journal of Mining, AJM, hereafter cited as EMJ) v.10, n.12, December 13, 1872. In the 1 February, 1868 issue of the AMJ there was a note from Nova Scotia about the general preference here for the Californian Stamp mill.

14.

¹⁴ The importance of mill buildings to the property's value, regardless of the gold production potential, was reflected in a dispute between V. Neily, Goldenville mine manager and J. B. Neily, the company's Boston president. Manager Neily recommended the sale of the additional mill building on the Goldenville property to raise capital to facilitate further developments underground. The president rejected the idea on the basis of the added value these buildings gave to the mining to support the operating costs. N. S. Department of Mines, Report OFR 1911, (Halifax, unpublished, 1911) p. 2; A. Heatherington, MINS, p. 11.

15.

¹⁵ Prospectus, Alpha Mining Company, Mount Unicake, p.12.

16.

¹⁶ B. Silliman, op. cit., p. 44.

17.

¹⁷ Industrial Advocate (Halifax), v.VII, n.5. March 1902, p. 8 - 9; v.VII, n.6,

April 1902, p. 9.

18.

¹⁸ Canada Census, 180 -'71.

19.

¹⁹ H. Y. Hunt, op. cit., According to this 1870 report it cost between $0.35 and $0.40 per ton of quartz crushed with water-power, including the interest on the capital cost of the mill, compared at $1.25 per ton of quartz with steam power.

S. P. Hunt. Op. cit., p. 15; Prospectus, Ophir Mining Company (p. 10). They installed a light engine to power its 8 stamp to reduce the original cost of crushing. The company eventually installed a water-powered mill and enlarged its mill from 8 to 16 stamps. The prospectus started that the new mill had dispensed with the cost of fuel, as water was available to operate day and night. Previous crushing costs ranged between $3.00 and $1.25 per ton.

20.

²⁰ T. S. Hunt, op. cit., p. 29 -30.

21.

²¹ Eastern Chronicle, (New Glasgow) 8 May 1862; A. Heatherington, Practical Guide…, p. 113. Heatherington had published a drawing of the 10 stamp mills produced by Moray and Sperry, New York, in his Halifax publication Mining Gazette. ILLUS. 5, following page of report.

22.

²² Prospectus, Ophir Mining Company, p. 11; "… there are several Nova Scotia foundries and one or more manufactories of engines and stamp mills…" The prospectus pointed out that the cost of local products was less than those produced in New England.

Hutchinson's Directory, Nova Scotia, 1864 - '65, p. 621, 617, 173 and 591.

Hutchinson's Directory, Nova Scotia, 1866 - '67; p. 103.

Hutchinson's Directory, Nova Scotia, 1864 - '65, p. 621, p. 626.

McAlipine's Directory, Nova Scotia, 1870 - '71, p. 599, p.50.

Halifax Sun, 23 June 1862. One of Goldenville crushers was manufactured by Mitchell in Halifax.

23.

²³ Encyclopedia Britannica, figure 5, p. 747.

24.

²⁴ T. S. Hunt, op. cit., p. 13.

25.

²⁵ B. Silliman, op. cit., p. ; J. A. Phillips, Gold Mining and Assaying: A Scientific Guide for the Australian Emigrant, (London: John J. Griffin, 1853)

p. 89 -90. The lifters or stamp stems, used in the Australian mills described by Phillips, consisted of wood.

26.

²⁶ Prospectus, Ophir Mining Company, p. 7; See also Hunt's description of the water-power mill built by Peter Montieth for this company at Ophir - T. S. Hunt, op. cit., for the mills at Goldenville.

27.

²⁷ W. Malcolm, op. cit.

28.

²⁸ T. S. Hunt, op. cit.

Mills constructed later on in the century were classified as heavy and light mills, according to the weight of stamps employed. The heavier mills with stamps of over 900 pounds had shorter drops that the lighter stamps. Because of the nature of gold, there were problems in over crushing the quartz and reducing the potential amount of the gold recoverable.

29.

²⁹ See W. Malcolm, op. cit.; H. Louis, op. cit. p. 24.

30.

³⁰ B. Silliman, op. cit., p.20 - 21. Messrs. Phillips and Darlington were named by Silliman as responsible for the English mills in the province. Phillips was most likely the same John A., the authority ington, op. cit., p. 109; Encyclopedia Britannica.

31.

³¹ T. S. Hunt, op. cit., p. 14. In the mills used in the latter years of the century, the quartz was fed into the back of the battery, however Heatherington states that it was fed into the front of the mill in these earlier mills. See A Practical Guide … p. 109

32.

³² H. Louis, op. cit., p. 207.

33.

³³ W. Malcolm, op. cit., p. 113 - 114.

34.

³⁴ T. S. Hunt, op. cit., p. 14.

35.

³⁵ A. Del Mar, op. cit., p. 20.

36.

³⁶ T. S. Hunt, op. cit., p. .

37.

³⁷ Morning Chronicle, (Halifax) 8 April 1862.

38.

³⁸ H. Louis, op. cit., p. 144.

39.

³⁹ Anonymous, A. Goldseeker's Guide …, p. 36. The author writes the following about operations at the Tangier gold mines: "…mercury has not yet [1862] been used in separating the gold, either here or at other locations." B. Silliman, op. cit.; T. S. Hunt, op. cit., p. 15, 16: "…a wooden battery is preferable when mercury is used…"

40.

⁴⁰ T. S. Hunt, op. cit., p. 15 - 16, "The amalgamation of gold in the batteries during pulverization is adopted in most of the mills in Nova Scotia. This requires the introduction of mercury into the boxes at regular intervals…" In this 1868 report Hunt also quoted the following passage from Phillips' The Mining and Metallurgy of Gold and Silver to explain the procedure for the employment of mercury:

"One ounce of gold required for its collection about an ounce of mercury; but when the gold is in a finely divided state, the addition of another quarter of an ounce is thought to be advantageous. The proper proportion is however, readily ascertained by watching the discharge, If any particles of amalgam, which must be introduced, but if, [on the contrary, they be soft and pasty, or if] globules of mercury make their appearance, the supply to the battery must be diminished. When the proportion of mercury has been properly adjusted, the amalgamation of gold is completely has been regularly introduced, and the rock contains coarse gold, from sixty to eighty per cent of the gold saved is caught in the battery; but when… the gold is in a very finely divided state, and is associated with ores of silver and other sulphides, the results are less satisfactory

41.

⁴¹ Encyclopedia Britannica, op. cit., p. 748.

42.

⁴² George Lawson, "On Some Recent Improvements in the Amalgamation Process for Extracting Gold from Quartz", Proceedings and Transactions of Nova Scotian Institute of Natural Science, v.I, Part 4, 1866, p.71-76.

43.

⁴³ S. P. Hunt, op. cit., p. 18; H. Louis, op. cit., p. 305-306.

44.

⁴⁴ W. Malcolm, op. cit., p. 93; E. Gilpin, "The Gold Fields of Nova Scotia"

(1882) p. 17; H.Y. Hind, Report on Waverley Gold District, (1869) p. 49.

45.

⁴⁵ T. S. Hunt, op. cit., p. 16.

46.

⁴⁶ Ibid, p. 16.

47.

⁴⁷ Ibid, p. 29.

48.

⁴⁸ Ibid, p. 29.

49.

⁴⁹ Eastern Chronicle, (New Glasgow) 26 June, 1862. The reporter covering the Wine Harbour gold fields noted in his dispatch"…the amalgamating process appears quite defective … as tailings appear to contain much gold".

50.

⁵⁰ W. Malcolm, op. cit., p. 93 and 112; H.Y. Hind, Report on the Waverley Gold District, (1869) p. 49: "…66% of the gold is recovered when there are arsenical iron ores within the quartz". Hind attributed the loss of the remainder by the following factors:

1. formation of spongy amalgam
2. the gold was covered with compound of the arsenic and thus escaped amalgamation.
3. it escaped in arsenides and sulphides of iron.
4. the gold escaped amalgamation as a result of being coated with grease from the miners' candles.

51.

⁵¹ Professor George Lawson, op. cit.

52.

⁵² Silliman, op. cit., (1864) p. 44.

53.

⁵³ Ibid. In the introduction to T. S. Hunt's 1868 report on the Nova Scotia gold fields, geologist A. Michel recommended the process of calcinations prior to amalgamation. op. cit., p. 8.

54.

⁵⁴ N. S. J.H.A., 1873, Appendix II, Mines Report, p. 25.

55.

⁵⁵ H. Y. Hind,… Sherbrooke (1870) p. viii "… the concentration of tailings by means of Buddles, Blanket Strakes, … is unknown… and the use of long sluices to save floured mercury is not practiced". W. Malcolm, op. cit., p. 112. The collapse of the gold mining attributed to the lack of technology to concentrate the tailing. There was not enough "free milling gold" available to make profitable returns. See M. Miller, "Men, Machines and Gold".

(unpublished paper, c. 1977 - '78)

56.

⁵⁶ Encyclopedia Britannica, p. 748.

57.

⁵⁷ T. S. Hunt op. cit., p. 16. The fire to melt the amalgam was made using alder in the earlier period, then coke. W. MacDonald, Oral Interview, 1978.