|
US2213641A
|
|
Cleaning powder
|
|
US2225540A
|
|
Powder container and applicator
|
|
US2210012A
|
|
Communication system
|
|
US1954462A
|
|
Metallic paint
|
|
US1862869A
|
|
Method of roasting ores and concentrates
|
|
US1920442A
|
|
Purification of solutions of zinc salts
|
|
US2017612A
|
|
Improvements in hydrometallurgical recovery of lead from ores and other lead bearing materials
|
|
US1864777A
|
|
Recovery of metals from zinc plant residue
|
|
US1839905A
|
|
Method of electrolysis
|
|
US1851219A
|
|
Method of electrodeposition of zinc
|
|
US1759494A
|
|
Method for the recovery of lead and other metals from ores or other lead-bearing materials
|
|
US1759493A
|
|
Method of electrolysis
|
|
US1739772A
|
|
Electrolytic precipitation of metals
|
|
US1858944A
|
|
Hydrometallurgical treatment of ores
|
|
US1570795A
|
|
Storage bin or hopper
|
|
US1623605A
|
|
Pump
|
|
US1587438A
|
|
Electrolytic recovery of metals from solutions
|
|
US1467516A
|
|
Process for the treatment and leaching of complex ores
|
|
CA198528A
|
|
Method of roasting ores
|
|
CA303359A
|
|
Method of electrolysis
|
