THE
SILVERSMITH’S HANDBOOK
BY THE SAME AUTHOR, UNIFORM WITH THE PRESENT VOLUME.
Ninth Impression, price 5s. net, cloth.
THE GOLDSMITH’S HANDBOOK,
CONTAINING
FULL INSTRUCTIONS FOR THE ALLOYING AND WORKING OF GOLD.
Including the Art of Alloying, Melting, Reducing, Colouring, Collecting, and Refining; The Processes of Manipulation, Recovery of Waste; Chemical and Physical Properties of Gold; with a New System of Mixing its Alloys, Solders, Enamels, and other Useful Rules and Recipes.
Crown 8vo, price 3s. 6d. net, cloth.
THE
HALL-MARKING OF JEWELLERY,
PRACTICALLY CONSIDERED.
Comprising an account of all the different Assay Towns of the United Kingdom, with the Stamps at present employed; also the Laws relating to the Standards and Hall Marks at the various Assay Offices; and a variety of Practical Suggestions concerning the Mixing of Standard Alloys, and other Useful Information.
CROSBY LOCKWOOD & SON,
7, Stationers' Hall Court, Ludgate Hill, E.C.
THE
SILVERSMITH’S HANDBOOK
CONTAINING
FULL INSTRUCTIONS
FOR THE
ALLOYING AND WORKING OF SILVER
INCLUDING THE DIFFERENT MODES OF REFINING AND MELTING
THE METAL; ITS SOLDERS; THE PREPARATION OF IMITATION
ALLOYS; METHODS OF MANIPULATION; PREVENTION OF
WASTE; INSTRUCTIONS FOR IMPROVING AND
FINISHING THE SURFACE OF THE WORK
TOGETHER WITH OTHER USEFUL
INFORMATION AND MEMORANDA
By GEORGE E. GEE
GOLDSMITH AND SILVERSMITH
AUTHOR OF “THE GOLDSMITH’S HANDBOOK,”
“THE HALL-MARKING OF JEWELLERY,” ETC. ETC.
Fifth Edition
Capio Lumen
LONDON
CROSBY LOCKWOOD AND SON
7, STATIONERS' HALL COURT, LUDGATE HILL
1921
PRINTED BY
WILLIAM CLOWES AND SONS, LIMITED,
LONDON AND BECCLES.
PREFACE.
The object of this Treatise is to supply a want long felt in the Silver Trade, namely, a work of reference from which workmen, apprentices, and manufacturers, employing the material upon which it treats, may find information which will be of assistance to them in the performance of their daily duties, and by which their operations may be rendered more successful. The Author was led to undertake the present work from having had many opportunities, during his lengthened experience in the art of silver-working, of observing the difficulties and stumbling-blocks that are constantly to be met with in the manifold branches of this important trade, by those practically engaged in it, and also by those persons who are desirous of acquiring a thorough knowledge of the mechanical and manipulative details belonging to it. To assist his object, numerous illustrations have been prepared for this Treatise, with the view of rendering the various processes of the art more readily comprehensible, and to save a lengthened or detailed description of them.
The different modes of alloying and melting silver; its solders; the preparation of imitation alloys; methods of working; the prevention of waste; instructions for improving and finishing the surface of the work, together with other useful information and memoranda—all these have been carefully collected and placed in order in the body of the work.
The Author has endeavoured, throughout, to present the contents (which he has with some little difficulty and labour brought together) in as practical and readable a form as is compatible with accuracy and efficiency.
G. E. GEE.
PREFACE TO THE SECOND EDITION.
Since the publication of the first edition of this work important changes have taken place in the commercial value of silver, its present cost in the best markets being sixpence per ounce lower than it was when this volume first appeared in 1877. This depreciation in value has, of course, necessitated a thorough revision of the former prices of the various alloys, solders, and other substances mentioned throughout the work; and this has been done in order to render it the more complete as a work of general reference, conveying correct and useful information to the reader. The Author trusts that his endeavours in this direction will be appreciated.
58, Tenby St. North, Birmingham.
February, 1885.
PREFACE TO THE FOURTH EDITION.
In issuing the present edition, a few introductory remarks are necessary to explain that numerous revisions have been made in Chapters VI. and VII. (by means of the Tables referred to below) regarding the cost prices of the different alloys, solders, etc., which I trust will increase the value of the book.
Through the repeal of the silver duty in the year 1890, a great impetus has been given to the Silver industry of this country, and notwithstanding the length of time that has elapsed since this book was first published, a steady demand has continued for its possession by workers in the precious metal trades—a fact which is gratifying to the Author, not only because a reprint is again called for, but as showing that the work has held its position, and may now justly claim to be a standard authority on the subject of which it treats.
It has not been found necessary to interfere with the general processes embodied in the book, as they are practically the same as formerly; but as regards the commercial value of silver, there is again a considerable depreciation[A] to record on the prices prepared for the second edition in 1885, and it becomes imperative that this depreciation should be dealt with in this new edition, in order to bring the work up to date.
The market price of silver has for many years been of a very variable nature, almost each day’s prices showing a difference, so that it would be impossible to provide the reader with an unvarying fixed price per ounce. The best and most practical thing to do under the circumstances, it seemed, was to carefully revise the different cost prices of the alloys and solders specified in Chapters VI. and VII. and give them by way of approximate Tables, compiled for each chapter separately. These two Tables follow this Preface (making pp. ix. and x.) and will serve as a ready reference for present workers in the silver trades. Thus, by bringing the figures down to date, the work may still retain its reliable character as a practical guide to the silversmith’s workshop.
G. E. GEE.
58, Tenby St. North, Birmingham.
January, 1907.
PUBLISHERS' NOTE TO FIFTH EDITION.
In February 1921 silver was quoted at 34½d. to 36-1/8d., and it is therefore sufficient to note that the prices at that date correspond approximately to those current in 1907. It should be noted that the melting of British gold and silver is prohibited, as well as their export.
Table of Revised and Up-to-date Cost Prices of the Different Alloys in Chapter VI.
Page. | No. and quality of alloy. | Cost price 1885. | Cost price 1907 and 1921. |
61 | Old standard alloy | For | 4/4 | per oz. | read | 2/9 | ½ | per oz. |
62 | New standard alloy | ” | 4/6 | ” | ” | 2/10 | ½ | ” |
64 | No. 1, silver alloy | ” | 4/2 | ” | ” | 2/9 | | ” |
64 | No. 2, silver alloy | ” | 3/9 | ” | ” | 2/5 | ½ | ” |
65 | No. 3, silver alloy | ” | 3/6 | ” | ” | 2/3 | ½ | ” |
65 | No. 4, silver alloy | ” | 3/3 | ” | ” | 2/1 | ½ | ” |
66 | No. 5, silver alloy | ” | 3/2 | ” | ” | 2/0 | ½ | ” |
66 | No. 6, silver alloy | ” | 3/1 | ” | ” | 2/- | | ” |
67 | No. 7, silver alloy | ” | 3/- | ” | ” | 1/11 | | ” |
67 | No. 8, silver alloy | ” | 2/10 | ” | ” | 1/10 | | ” |
70 | French coinage alloy | ” | 4/2 | ” | ” | 2/9 | | ” |
70 | French plate alloy | ” | 4/5 | ” | ” | 2/10 | | ” |
70 | French 0·800 alloy | ” | 3/9 | ” | ” | 2/5 | ½ | ” |
72 | German coinage alloy | 0·900 standard | ” | 2/9 | | ” |
72 | German silver wares alloy | 0·950 1st standard | ” | 2/10 | ¼ | ” |
73 | Ditto | 0·800 2nd | ” | ” | 2/5 | ½ | ” |
73 | Ditto | 0·750 3rd | ” | ” | 2/3 | ½ | ” |
This Table is based on the market price of fine silver being 3/- per ounce.
Table of Revised and Up-to-date Cost Prices of the Different Solders in Chapter VII.
Page. | Quality of solder. | Cost price 1885. | Cost price 1907 and 1921. |
78 | Hardest silver solder | For | 3/9 | per oz. | read | 2/5 | per oz. |
79 | Hard silver solder | ” | 3/6 | ” | ” | 2/3 | | ” |
79 | Easy silver solder | ” | 3/2 | ” | ” | 2/0 | | ” |
81 | Best silver solder | ” | 3/9 | ” | ” | 2/5 | | ” |
82 | Medium silver solder | ” | 3/6 | ” | ” | 2/3 | | ” |
82 | Easy silver solder | ” | 3/3 | ” | ” | 2/1 | | ” |
83 | Common silver solder | ” | 3/- | ” | ” | 1/11 | | ” |
84 | Enamelling silver solder | ” | 3/9 | ” | ” | 2/5 | | ” |
84 | Ditto | ” | 3/2 | ” | ” | 2/0 | | ” |
84 | Filigree solder | ” | 3/9 | ” | ” | 2/5 | | ” |
85 | Quick-running silver solder | ” | 3/- | ” | ” | 1/11 | | ” |
85 | Silver solder for chains | ” | 3/- | ” | ” | 1/11 | | ” |
85 | Easy solder for chains | ” | 3/- | ” | ” | 1/11 | | ” |
85 | Common silver solder | ” | 2/9 | ” | ” | 1/9 | | ” |
86 | Common easy solder | ” | 2/9 | ” | ” | 1/9 | | ” |
86 | Arsenic silver solder | ” | 3/9 | ” | ” | 2/5 | | ” |
86 | Ditto | ” | 3/6 | ” | ” | 2/3 | ½ | ” |
86 | Easy silver solder | ” | 3/2 | ” | ” | 2/0 | ½ | ” |
87 | Common easy silver solder | ” | 2/9 | ” | ” | 1/9 | | ” |
This Table is based on the market price of fine silver being 3/- per ounce.
CONTENTS.
INTRODUCTORY CHAPTER.
| Page |
Silver a Precious Metal | 1 |
Economy of Treatment | 1 |
Working Silversmiths | 2 |
English and Foreign Workmen | 2 |
Technical Education | 2 |
Pure Silver | 3 |
Plate and Ornamental Wares | 4 |
CHAPTER I.
Silver.
Silver, Characteristics of | 5 |
Silver for Filigree Work | 5 |
Indian Filigree Workers | 5 |
Malleability of Silver | 6 |
Ductility of Silver | 6 |
Test for Pure Silver | 6 |
Silver known to the Ancients | 6 |
Silver Currency | 6 |
Polished Silver | 7 |
Tarnishing of Silver | 7 |
Density of Silver | 7 |
Fusibility of Silver | 7 |
Heating Power of Silver | 7 |
Action of Silver under Great Heat | 8 |
Hardness of Silver | 8 |
Nitrate of Silver | 8 |
Silver resists Aqua-regia | 8 |
Chief Places of Filigree Manufacture | 8 |
Chief Uses of Silver | 9 |
Price of Silver, Commercial | 9 |
Ores of Silver | 9 |
Dissolution of Silver | 9 |
Caustic Alkalies | 10 |
Nitre | 10 |
Vegetable Acids | 10 |
CHAPTER II.
Sources of Silver.
Silver-mining | 11 |
Great Britain | 11 |
British Isles' Yield of Silver | 11 |
Spain | 11 |
America | 11 |
Native Silver | 11 |
European Supplies of Silver | 12 |
American Supply of Silver | 12 |
The Richest Mine | 12 |
State of the Jewellery Trade | 12 |
Yield of Silver | 13 |
Foreign Silver Currency | 13 |
Chief Sources of British Silver | 13 |
State in which it is found | 14 |
CHAPTER III.
The Assay of Silver Ores.
Silver and Mercury | 15 |
Assaying of Silver Ores | 16 |
Crucible Assay | 16 |
Fluxes for Crucible Assay | 16 |
Assay of Genuine Silver Ores | 16 |
Carbonate of Soda | 16 |
Dimensions of Crucible | 16 |
Litharge | 17 |
Preparation and Charge for Assay | 17 |
Treatment in the Furnace | 18 |
Casting-mould | 18 |
Scorification Process | 18 |
Fusing Cup or Scorifier | 19 |
Special Form of Scorifier | 19 |
Scorification Assay the Reverse of Crucible Assay | 19 |
Charge for Scorification Assay | 20 |
Advantages of the Process | 20 |
Anthracite and its Object | 21 |
Separation of the Silver from the Slag | 21 |
Borax, use of, in Assaying | 22 |
Continental Method of Assaying | 22 |
Flux and Charge for Crucible | 23 |
Details of the Process | 23, 24 |
Skittle-pot | 25 |
Cupellation | 26 |
Cupel, its Mode of Manufacture | 26 |
Cupel-mould | 27 |
Assayer’s Muffle | 28 |
Cupel-tongs | 28 |
Brightening | 29 |
Sprouting | 29 |
Weighing of Silver Assay | 30 |
Chief Alloy of Silver | 30 |
CHAPTER IV.
The Cupellation of Silver Ores.
Test-ring | 31 |
Preparation of Bone-ash | 32 |
Defects in Bone-ash Cupel | 33 |
Currents of Air to the Furnace | 33 |
Withdrawal of the Silver from the Cupel | 34 |
Removal of the Litharge, Manner of | 35 |
Quantity of Alloy per Cupel | 35 |
Purity of Silver after Cupellation | 37 |
Ancient Method of Assaying | 37 |
Dr. Lamborn on Assaying | 38 |
Scriptural Testimony | 37, 38 |
English System of Assay | 39 |
CHAPTER V.
The Alloys of Silver.
Silversmith’s Alloys | 40 |
Filigree Work | 40 |
Alloy | 41 |
Amalgam | 41 |
Metals employed in the Industrial Arts | 41 |
Metals, their various Characteristics | 41 |
Principal Alloys of Silver | 42 |
Copper | 42 |
Characteristics of Copper | 43 |
Protoxide of Copper | 44 |
Action of Acids on Copper | 44 |
Bean-shot Copper for Alloying | 44 |
Chemical name for Copper | 44 |
Nickel | 45 |
Cronstedt | 45 |
Density of Nickel | 45 |
Ductility of Nickel | 45 |
Malleability of Nickel | 45 |
Fusibility of Nickel | 45 |
Nickel Coinage | 45 |
Nickel Alloys | 46 |
Electro-plate | 46 |
Zinc | 46 |
Spelter | 46 |
Zinc in Silver Solder | 46 |
Annealing of Zinc | 47 |
Specific Gravity of Zinc | 47 |
Spelter used by Jewellers | 47 |
Tarnishing of Zinc | 47 |
Malleability of Zinc | 48 |
Ductility of Zinc | 48 |
Tenacity of Zinc | 48 |
Tin | 48 |
Ancient Workers in Tin | 48 |
Density of Tin | 48 |
Christianity and Tin | 48 |
Fusibility of Tin | 48 |
Dissolving of Tin | 48 |
Tin alloyed with Gold | 49 |
Tin alloyed with Silver | 49 |
Tin in Silversmith’s Solders | 49 |
Vapours of Tin injurious to Gold | 49 |
Malleability of Tin | 49 |
Ductility of Tin | 49 |
Tenacity of Tin | 49 |
Scientific Name for Tin | 50 |
Table of Metallic Elements | 50 |
Melting-points of the Principal Metals | 51 |
Physical Properties of the Principal Metals | 51 |
CHAPTER VI.
Various Qualities of Silver.
Mechanical Uses of Silver | 52 |
Filigree Work | 52 |
Birmingham | 52 |
London | 52 |
Indian | 53 |
Chief Places of Filigree Manufacture | 53 |
Continental Cheap Labour | 54 |
Hand-made Articles | 54 |
Process of Workmanship | 55 |
Maltese Filigree | 55 |
Chinese and Japanese Filigree | 56 |
Filigree of Norway and Sweden | 56 |
Filigree working, Necessity for Pure Metal | 56 |
Old Method of making Filigree | 57 |
Twisting of the Wire | 58 |
Lathe, Use of | 58 |
Flattening of Twisted Wire for Filigree | 59 |
New Method of preparing Filigree Wire | 59 |
English Standards for Silver | 60 |
English Coinage | 61 |
Standard Silver Alloy | 61 |
Alloy for Hall-marking | 62 |
Standard Alloy of the Highest Quality | 62 |
Standard Alloy for Hall-marking | 62 |
Alloy commonly used in England | 63 |
Qualities used by English Silversmiths | 63 |
Drawbacks to Hall-marking | 63 |
Method of calculating the Qualities of Silver | 63 |
Silver Alloy No. 1, cost 4s. 7d. per oz. | 64 |
” No. 1, differently calculated | 64 |
” No. 2, cost 4s. 1d. per oz. | 64 |
” No. 2, differently calculated | 64 |
” No. 3, cost 3s. 10d. per oz. | 65 |
” No. 3, differently calculated | 65 |
Silver Alloy No. 4, cost 3s. 7d. per oz. | 65 |
” No. 4, differently calculated | 65 |
” No. 5, cost 3s. 6d. per oz. | 66 |
” No. 5, differently calculated | 66 |
” No. 6, cost 3s. 3d. per oz. | 66 |
” No. 6, differently calculated | 66 |
” No. 7, cost 3s. 2d. per oz. | 67 |
” No. 7, differently calculated | 67 |
” No. 8, cost 3s. per oz. | 67 |
” No. 8, differently calculated | 67 |
Instructions in the Preparation of Alloys | 68 |
Copper for Alloying | 68 |
French Standards | 69 |
Silver Ware | 69 |
Coinage | 69 |
French Alloy for Coinage | 70 |
French Alloy for Plate | 70 |
French Alloy for Silver Ware | 70 |
Instructions in the Preparation of these Alloys | 70 |
German Standards | 71 |
Silver Ware | 71 |
Coinage | 71 |
Silver Alloy for the German Coinage | 72 |
Alloy for Plate | 72 |
Alloys for Silver Wares | 72, 73 |
Law on the Manufacture of Silver Wares | 73 |
Remedy allowed in Fineness | 73 |
Government Exports | 73 |
Guarantee Marks | 73 |
CHAPTER VII.
Silver Solders: their Uses and Applications.
The Act of Soldering | 74 |
Cause of Inferior Manufactures | 74 |
Tin in Solders | 75 |
Filed Solders | 76 |
Zinc in Silver Solder | 76 |
Solders made with Copper and Silver | 76 |
Hard Silver Solders | 77 |
Medium Solders | 77 |
Easy Solders | 77 |
Connections for Soldering | 77 |
Flux for Soldering | 77 |
Fusibility of Silver Solders | 78 |
Hardest Silver Solder, cost 4s. 1d. per oz. | 78 |
Ditto, differently calculated | 79 |
Medium Silver Solder, cost 3s. 10d. per oz. | 79 |
Ditto, differently calculated | 79 |
Easy Silver Solder, cost 3s. 5d. per oz. | 79 |
Ditto, differently calculated | 80 |
Remarks on Silver Solders | 80 |
Composition for Solder | 81 |
Best Hard Solder, cost 4s. 1d. per oz. | 81 |
Ditto, differently calculated | 81 |
Medium Solder, cost 3s. 10d. per oz. | 82 |
Ditto, differently calculated | 82 |
Easy Solder, cost 3s. 7d. per oz. | 82 |
Ditto, differently calculated | 82 |
Common Solder, cost 3s. 3d. per oz. | 83 |
Ditto, differently calculated | 83 |
Directions on the Melting of Solders | 83 |
Solder for Enamelling, cost 4s. 1d. per oz. | 84 |
” ” cost 3s. 6d. per oz. | 84 |
Easy Solder for Filigree Work | 84 |
Quick Running Solder, cost 3s. 3d. per oz. | 85 |
Silver Solder for Chains, cost 3s. 3d. per oz. | 85 |
Easy Solder for Chains, cost 3s. 3d. per oz. | 85 |
Common Silver Solder, cost 3s. per oz. | 85 |
Common Easy Solder, cost 3s. per oz. | 86 |
Arsenic Solder, cost 4s. 1d. per oz. | 86 |
Silver Solder with Arsenic, 3s. 10d. per oz. | 86 |
Easy Silver Solder, cost 3s. 6d. per oz. | 86 |
Common Easy Solder, cost 3s. per oz. | 87 |
Another Common Solder | 87 |
Very Common Solder | 87 |
Directions in the Preparation of Solders | 87 |
Drossy Solders | 88 |
Mode of Soldering Gold and Silver | 88 |
Pallion Solder | 88 |
Blowpipes | 89 |
Solder-dish and Charger | 89 |
Soft Solder | 90 |
Art in Soldering | 90 |
Solder for Filigree | 91 |
Lemaille Solder | 91 |
English Filigree Workers | 91 |
Sprinkle Borax | 92 |
Special Soldering Flux | 92 |
Boiling-out Pickle | 93 |
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 |