Sentence examples for before smelting from inspiring English sources

Crushing and screening are straightforward mechanical operations that do not alter an ore's composition, but some ores need to be upgraded before smelting.

In modern ore treatment, various preliminary steps are usually carried out before smelting in order to concentrate the metal ore as much as possible.

He describes the assaying of ores, the methods used for enriching ores before smelting, and procedures for smelting and refining a number of metals; and he concludes with a discussion of the production of glass and of a variety of chemicals used in smelting operations.

In the tin mines, in which ore could be crushed far more finely than copper before smelting, cobbing and bucking did not take place.

The deposits had been known and worked for centuries before 1867, when Scottish missionary and explorer David Livingstone described the smelting of ore into 50- to 100-pound (22.5- to 45-kg) ingots by Katanga-area peoples.

488, where a state tax imposed on mineral ore exported from the state before being smelted was held to be a tax on interstate commerce, no such tax being imposed on like ore reduced within the state.

Before being smelted, low-grade concentrates from complex ores are first roasted in a reverberatory or multiple-hearth furnace at temperatures between 550 and 650 °C (1,025 and 1,200 °F) to drive off the sulfur.

Amalgam recovered after washing was dried before being smelted to recapture the mercury and silver, which was added back to new batches of ore.

Someone else was smelting silver hundreds of years before the Incas arrived.

He and his wife ran a rooming house during the Depression before he settled into an engineering career, specializing in building smokestacks for smelting metal.

In smelting production workshops, the air concentration of Mn ranged in 0.36~1.06 mg/m before 2007, and then decreased in 0.08~0.45 mg/m after 2007.