Bismuth: Sweated Out of Native Ore in Inclined Iron Tubes, the Schneeberg Way (Thorpe, 1912)

The old way of getting bismuth from ore that holds it as the metal: heat the lumps just enough in sloping iron tubes and the bismuth, which melts easily, runs out of the rock into pots under charcoal. It takes 30-60 minutes a charge but gets only about two-thirds of the metal. Not given: the furnace temperature. Source: E. Thorpe, Dictionary of Applied Chemistry vol. I (1912), Bismuth, p. 458. Picture: Thorpe's Fig. 1, the furnace in plan.

中级

30-60 minutes per charge

说明

Pick and break the ore

Sort the ore (7-12 % bismuth) by hand from the waste rock as far as possible and break it into pieces the size of a hazel nut.

此步骤所需材料：

自然铋矿石1 12 cwt per tube charge

所需工具：

锤子

工业平台秤

Charge the tubes

Load about 12 cwt into each inclined iron tube of the furnace, leaving room to stir from the upper end. Close the upper ends with iron plates and the lower ends with plates pierced with round holes. Under each lower end stand an iron pot holding powdered charcoal, kept gently warm by a small charcoal fire.

此步骤所需材料：

木炭1 powdered, in the pots and for the pot fire

所需工具：

铋熔析炉

铸铁坩埚

Sweat out the bismuth

Fire the furnace with wood so that the metal flows easily. In about 10 minutes the bismuth begins to run into the pots, where the charcoal covers it from the air. Stir the ore now and then with an iron rod from the upper end; in 30-60 minutes the charge is done. 20 cwt of ore burns about 63 cubic feet of wood.

此步骤所需材料：