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CHAPTER VIII.

On the Melting of Silver.

Directions on Melting	94
Weighing Metal for the Crucible	94
Crucibles	95
Best Crucibles to employ	95
Fluxes: their Action on Crucibles	96
Fluxes employed in Melting	96
Testing the Soundness of a Crucible	97
Mixing various Metals for melting	97
Zinc a fusible Metal	98
Charcoal	99
Bad working Material	99
Plumbago Crucible for Melting	99
Tongs for Melting	100
Ingot-mould	100
Flux and the Pouring of Molten Metal	101
Protoxide of Zinc	102
Scrap Silver	102
Carbonate of Soda	102
Dissolving Impurities	103
Lead and Tin in Silver	103
Sal-ammoniac	103
Lemel	103
Mixture prepared for Crucible	104
Burning of Lemel	104
Skittle-pot for Lemel	104
Melting of Lemel	105
Another Mode of melting Lemel	106
Crucible for Lemel	106
Pouring of Lemel from Crucible	107

CHAPTER IX.

On the Working of Silver.

Rolling Silver	108
Annealing Silver	109
Irregularities in Rolling-mills	110
Messrs Kemp’s Mill	110, 111
Table of the Cost of Silver-rolling	112
Slitting Rollers	112
Breaking-down Rollers	112
Wire-rolling	113
Wire-drawing	113
Draw-plate	114
Draw-bench	110, 115
Draw-tongs	115
Drum used by Wire-drawers	115
Fine Wire-drawing	115, 116
Wire-drawer’s Punch and Hammer	117
Wrought Work	118
Sparrow-hawk	119
Raised Work	120
Cement for Chasers	121
Snarling-tools for Raising	122
Art in the Silver Trade	123
Burnished Silver Work	124
Silver Filigree Work	125
Stamped or Struck-up Work	126
Press	127
Plain Solid Work	127
Chain Bracelets	128
Present State of Silver Trade	128
Silver, Liability to become tarnished	129
Enamelling	129
Galvanic Ring	129
Mode of preparing Ring	129, 130
Hollow Silver Work	131
Stamping-press	132
Spinning	134, 135
Polishing	135
Water-of-Ayr Stone	136
Polishing-lathe	137
Washing-out Mixture	138

CHAPTER X.

Enriching the Surfaces of Silver.

Production of the best and richest Surface	139
Oldest Method for Whitening	140
East Indian Silversmiths	141
Indian Mode of Whitening Silver	142
Another Mode of Whitening	142
Boiling-out Pan	143
Boiling-out Mixture	143, 144
Our Mode of Whitening	145
Surface Refining of Silver	146
Brown Colour on Silver Goods	146
Common Articles of Silver	147
Whitening Powder or Mixtures	147
Nitrate of Silver Mixture	148
Improving the Colour of Electro-plate	149
Electro-plating	149
Discoverer of Electro-plating	149, 150
Constant Battery	150
Best Battery for Plating	151
Strength of Battery Solution	151
Bunsen’s Battery	152
Exciting Mixture for Battery	152
Zinc Amalgamation	153
Conducting Wires	154
Preparation of Plating Solution	155
Cyanide Solution	156
Black Cyanide	157
Strength of Plating Solution	157, 158
Inferior Plating Solution	159
Recovery of Silver from Plating Solutions	160
Scratch-brushing	161
Scratch-brush Lathe	161
Burnishing Silver Work	161, 162
Oxidizing Silver Work	163
Solution No 1.	163
Solution No 2.	164
Solution No 3.	164
Producing various Shades	165

CHAPTER XI.

Imitation Silver Alloys.

Melting Imitation Alloys	166
Common Silver Alloy	167
Another	167
Another	168
Another	168
Another	168
Another	168
Another	169
Another	169
Another	169
Another	169
Another	170
Another	170
Chinese Silver	170
Imitation Silver	170
Another	171
Another	171
Another	171
Another	171
White Alloy	172
Clark’s Patent Alloy	172
White Alloy	172
Alloy with Platinum	172
Alloy with Palladium	173
Uses for Imitation Alloys	173
Characteristics of Imitation Alloys	174

CHAPTER XII.

Economical Process.

Working Loss	175
Lowest Estimate Real Loss	175
Total Working Loss	176
Shop Floors	177
Waste-saving Precautions	177, 178
Treatment of Waste	178
Burning of Polishings	179
Treatment of Waste Liquids	180
Processes for the Recovery of Silver from Waste Waters	180, 182
Chloride of Silver	183
Aqua-regia	183
Precipitating Silver in Waste Waters	183
Solution for Precipitation	184
Sediment in Collecting-vessels	185

CHAPTER XIII.

Licences and Duties.

Acts of the Legislature	186
43 George III., c. 69	186
6 George I., c. 11	187
31 George II., c. 32	188
32 George II., c. 14	188
24 George III., c. 53	188
37 George III., c. 90	188
44 George III., c. 98	189
55 George III., c. 185	189
Table of Various Duties	189
Manufactured Plate	190
Remarks on the Licence Question	191, 196
Act of Parliament in Licences	193
Clause of Act	193, 194
Tax or Licence unjustly Assessed	195, 196

CHAPTER XIV.

Useful Information for the Trade.

Silversmith’s Alloys	197
Silver Wares	197
Cleaning Plate	198
Imitation Silver	198
Another	198
Removing Gold from Silver Articles	198
Oxidizing Silver	198
Dipping Mixture	199
Silver Powder for Copper	199
Powder for Silver	200
To protect the Polish of Metals	200
Silver-stripping Mixture	200
Stripping Silver	201
Soft Solder	201
Soldering Fluid	201
Dissolving Silver	202
Dissolving Silver Alloy	202
Dissolving Copper	202
Dissolving Soft Solder	202
Dissolving Silver Solder	202
Dissolving Sealing-wax	202
Resist Varnish	202
Plate Powder	202
Electro-plating Soft Solder	202
Another Recipe	203
Testing Silver Wares	203
Another Test	204
Perchloride of Iron	205
Aluminium Alloy	205
New Alloy	205
Removing Gold from Silver Wares	205
Silver Plating Fluid	206
Plate-cleaning Powder	206
Solder for Aluminium	206

CHAPTER XV.

Foreign Silver Standards	207
French Work, Duty on	208
Continental Silversmiths	209
French Style of Work	209
German Style of Work	210
Indian Style of Work	210
Austrian Style of Work	211
English Style of Work	211
Index	212

THE

SILVERSMITH’S HANDBOOK.

INTRODUCTORY CHAPTER.

In reviewing the rise and progress of the silversmith’s beautiful and interesting art, in its relation to the manufacture of articles of personal ornament and luxury at home and abroad, we may observe at the outset, that the material of which they are composed differs widely in character from that employed by the ordinary “metalsmiths” and the manufacturer of “electro-plated wares.” Silver, the material of which we are now treating, being a precious metal and of considerable value, it is essentially necessary that the most careful means be exercised in dealing with it from the commencement—that is, from the pure or fine state—and also that the utmost economy be observed in reference to the kind of mechanical treatment to which it is subjected in the production of the silversmith’s work, in order to prevent too great a quantity of waste or loss of material. For it should be borne in mind that silver, like gold, begins to lose, in one way or another, every time it is touched; therefore, carefulness and economy will be the characteristics of our teaching, so far as regards the present subject.

The vast majority of working silversmiths know very little of the physical and chemical properties of the metal they employ, and still less of the comparison it bears with other metals in the field of science; and this want of scientific knowledge is nowhere more apparent than in our own country, where the English workman, in art education, is much behind the foreigner; and yet we have some of the finest and best workmen, in their special branches, in the whole world. The English workman believes that if the work is worth doing at all, it is worth doing well; and we have no hesitation in saying, that, if a good technical education were afforded, concerning the precious metal trades, he would scarcely have an equal, and certainly no superior, abroad, in art workmanship, both in respect to the display of good taste and judgment, combined with a knowledge of design, so far as the exercise of these qualities is compatible with the manufacture of articles specially designed for use and ornament.

The object of the information we are about to supply is to enable the practical silversmith to become a perfect master of his art or profession; and such a condition, when once achieved, will be found of considerable assistance to him in the various kinds of manufacture that present themselves; so that he will know how to begin a piece of work and when to leave it off; be able to remedy a defect in the metal when required, as well as be in a position to form an opinion as to the relative treatment of its different alloys; all of which invariably require different treatment.

We shall commence by describing the characteristics of fine silver, carefully narrating the distinctive features of its alloys; then give an account of the processes employed, mechanical and chemical, in the silversmith’s workshop; and conclude by pointing out the difference between English and foreign work in regard both to style and workmanship.

It may be thought by the reader, if uninitiated in the art, that the costly plate and other articles made from the precious metal are manufactured from entirely pure silver, and therefore that they possess absolute freedom from alloy; but this is not the case. Pure silver being far too soft to stand the necessary wear and tear of (metallic) life, it is mixed with some other metal, to give it increased hardness. In the manufacture of plate and ornamental wares the metal employed is always copper, in various proportions, thus forming different commercial qualities; and of these we shall speak hereafter. Our first object is to treat of the chemical and physical properties of the pure metal.

CHAPTER I.

Silver.

Pure silver is, next to gold, the finest metal, but of a smoother and more polished nature. It may be said to be almost infinitely malleable, but it will not so easily yield or extend under the hammer as fine gold. As a malleable metal, however, it stands next to it in this respect. It is characterized by its perfectly white colour, being the whitest of all the metals. It is harder than gold, yet in a pure state it is so soft that it can easily be cut with a knife. On account of its extreme softness, when in a pure state, it is employed for filigree work, being utterly devoid of that elastic power which is found in the metal when alloyed. It is for this reason that the Indian filigree workers, who are the finest in the world, are so very particular about the absolute purity of the metal before commencing the manufacture of their artistic work; all of which is exceedingly beautiful.

It is reported that fine silver is capable of being beaten into leaves of less than one-hundred-thousandth part of an inch in thickness. For the accuracy of this statement we cannot vouch, never having had occasion to try the experiment; its employment in that form being unknown in the ordinary industrial pursuits. Fine silver is extremely ductile, and may be drawn into the very finest wire without breaking, and almost without annealing. Its purity can be partly ascertained by the latter process; for perfectly fine silver never changes colour by heat, whereas when it contains alloy it blackens if heated in contact with a current of air, and soon hardens in wire-drawing.

Silver was a metallic element known to the ancients, and it is repeatedly mentioned in the Holy Scriptures. In the time of the patriarchs we read of it as having been constantly employed in the transactions of nations, and that it was in use as a standard of value; thus forming a circulating medium for the purpose of exchange. This function it has always continued to fulfil down to the present day, except that since the year 1816 it has not been so employed in the English currency. However, as token money, it is everywhere recognised as a circulating medium of trade. The Egyptian symbol for silver was represented by Fig. 1, relating to the moon; in modern chemistry it is understood by ag. from the Latin name argentum, denoting silver.