Recovering Precious Metals from Waste Liquid Residues

Originally published in 1920, this book is written by a practical man, for practical men employed in the different branches of the precious metal industries of the nation, and the author has given full detailed descriptions of the processes and formulas, with illustrations of the apparatus to be severally employed in extracting the waste metals from all kinds of liquids, so as to make the book of special value to all concerned in the manufacture of jewellery and other kindred wares.

The object in writing the book has been to present the reader with a thoroughly practical account of the simplest and most accurate methods of recovering the gold, silver, and platinum from the sundry waste liquid residues of goldsmiths, silversmiths, and other workers in the precious metal trades, and thereby provide a long felt want for the direct guidance of practical men engaged in the different kinds of manufacturing establishments wherein the precious metals are employed.

"The author has had a large workshop training and practice, likewise an extensive commercial experience in the treatment of waste jewellery products, and has devised apparatus and methods hitherto unknown in manufacturing establishments, which are easy of execution and certain in their action; they are useful alike to the small as well as to the large manufacturer, and do not necessitate the employment of expensive chemicals or elaborate machinery to effect good results. He has treated the subject systematically, by proceeding in regular order with the different classes of wastes, so as to make the work available for all trades in which the precious metals are employed. This of necessity causes a certain amount of repetition, but for the sake of clearness it could not well be avoided.

A noted feature of the work is its simplicity of language, all technical terms and phrases, when made use of, being explained, so that the least informed operative may be able to comprehend the meaning and carry out the different operations to a most successful conclusion, and with a full appreciation of the possible results.

It now only remains to be stated that all the processes have been dealt with from an entirely practical point of view commercially, including such methods as the writer has found to give the best results in his own workshop, and it is hoped the numerous questions which for some years have been addressed to him regarding the difficulties that repeatedly arise in manufacturing establishments, will have their remedies provided for in these pages in a thoroughly sound and satisfactory manner. This is the only practical treatise on the subject."

Contents Covered:

• Preface
• Introduction
• Recovering Gold from Colour Waste
• The Copperas Process
• The Zinc Process
• The Old Iron Binding-Wire Process
• The Complex Process
• Recovering Gold from Electro-Gilding Waste
• The Zinc-Acid Process
• Recovering Gold from Rinsing Waters and Wash Waters
• The Hydrogen Sulphide Process
• Recovering Gold from Dip-Gilding Waste
• Recovering Gold from Old Stripping Solutions
• Recovering Gold from Photographer's Old Toning Solutions
• Useful Hints and Tables
• Gold Precipitating Reagents
• Recovering Silver from Silver-Plating Solutions
• The Zinc-Acid Process
• The Sulphide of Sodium Process
• Reducing Silver Sulphide to Metal
• Recovering Silver from Electro-Silvering Rinsing Waters
• Reducing Chloride of Silver to Metallic Silver with Metallic Iron
• Recovering Silver from Dip-Silvering Solutions and Their Rinsing Waters
• Recovering Silver from Old Stripping Solutions
• Recovering Silver from Nitric Acid Solutions; The Metallic Copper Process
• Washing Precipitates
• Recovering Silver from Glass Mirror Makers' Solutions
• Recovering Silver from Photographers' Old Hypo Solutions
• Recovering Silver from Sundry Salts of Silver
• Silver Precipitating Reagents
• Recovering Silver from Mixed Solutions
• Recovering Platinum from Platinum Solutions
• Recovering Platinum from Electro-Platinating Solutions
• Separating Platinum from Gold United by Soldering in a Manner That Both Metals Can Always Be Distinguished
• Separating Platinum from Gold
• Separating Platinum from Silver in Dental Alloy
• Separating Platinum from Copper
• Separating Platinum from Lemel without Any Gold in It
• Separating Platinum from Lemel Containing Both Gold and Silver
• Separating Platinum from Gold, Silver, Copper, Nickel, and Other Metals
• The Assaying of Platinum Wares
• Platinum Precipitating Reagents
• Recovering Gold, Silver, and Platinum from Waste Liquid Residues of Every Description by One Operation
• The Electrolytic Method
• Melting Sedimentary Residues
• Index