International Hallmarks on Silver
Tardy
- 01 juli 1995
- 9782901622178
Samenvatting:
INTERNATIONAL HALLMARKS ON
SILVER
General. Silver is one of the oldest metals known and it has been used for thousands of years.
It is found in the subsoil all over the world either in native form, veins or dendrites, silver sulphide or argyrose, or as a double sulphide of silver and copper: S Ag S Cu², or again as a double sulphide of silver and iron: S-Ag² 2S³ Feª, or finally as argentiferous galena.
In France, silver deposits are or were found in Huelgoat, Pontpean and Poullaouen in Brittany; Saint-Jean-d'Auxel, Giromagny and Sainte-Marie-aux-Mines in the Vosges; Durfort, Fournial, Pontgibaud and Villefort in the Massif Central; Stein-tein in the Pyrenees; Allemont, Argentière, the Challanches and Pescyen in the Alps; Vialas in Ardèche; and Largentière in the Ardèche, Confolens, Melle, The Bormettes and Peyre-brune.
Among the other European countries silver is found in Germany: Saxony and the Hartz; in Spain: Estramadura & Ingena; in Finland; in Greece: Laurium; in Italy: Sardinia; LaNorway; in Romania; Transsylvania; and in Sweden, In Asia it is found in the Urals, the Altai mountains, Tongkin,
Annam, Iran and Japan. un Africa silver is produced in Algeria, Tunisia, Morocco, the Congo region, Rhodesia and the Transvaal.
In Oceania it is produced in New South Wales, New Guinea and New Zealand.
In North America silver is mined in the Rocky Mountains of Nevada and in Canada; in Central America in Mexico: in South America in Chile, being found in native form in Ata-cama and Potosi where its concentration reaches 40%; and also in Bolivia (Tarapace), and in Argentina in the La Plata mines.
The main producers are the United States, Mexico, Bolivia, Peru and Chile.
Silver extracted from the mine has to be refined. With 1/1000 of selenium it is breakable, while traces of tellurium or bismuth prevent it from being rolled. Virgin silver contains gold, platinum and palladium which make refining it profitable.