The bullion left in the retorts is then melted in black-lead crucibles, with the addition of small quantities of suitable fluxes, e.g.
Moulds for reproducing plates or art-work are often taken in plaster, beeswax mixed with Venice turpentine, fusible metal, or guttapercha, and the surface being rendered conductive by powdered black-lead, copper is deposited upon it evenly throughout.
Earlier names, still in common use, are plumbago and black-lead, but since the mineral contains no lead these names are singularly inappropriate.
In 1778 he proposed a new method of making calomel and powder of algaroth, and he got molybdic acid from mineral molybdaena nitens which he carefully distinguished from ordinary molybdena (plumbago or black lead of commerce).
Budweis has a large, varied and growing industry, which comprises the manufacture, of chemicals, matches, paper, machinery, bricks and tiles, corn and saw mills, boat-building, bell-founding and black-lead pencils.
