The Collaborative International Dictionary
massicot \mas"si*cot\, n. [F. massicot; E. masticot is a corruption.] (Chem.) Lead monoxide (also called Lead protoxide), PbO, obtained as a yellow amorphous powder, the fused and crystalline form of which is called litharge; lead ocher. It is used as a pigment. It is also called lead oxide yellow, as opposed to red lead, which is lead tetroxide Pb3O4.
Note: Massicot is sometimes used by painters, and also as a drier in the composition of ointments and plasters.
Wiktionary
n. lead monoxide#English (PbO) a toxic solid formed from the oxidisation of lead in air, and used as a pigment
Wikipedia
Litharge (from Greek lithargyros, lithos (stone) + argyros (silver) λιθάργυρος) is one of the natural mineral forms of lead(II) oxide, PbO. Litharge is a secondary mineral which forms from the oxidation of galena ores. It forms as coatings and encrustations with internal tetragonal crystal structure. It is dimorphous with the orthorhombic form massicot. It forms soft ( Mohs hardness of 2), red, greasy-appearing crusts with a very high specific gravity of 9.14–9.35. PbO may be prepared by heating lead metal in air at approximately 600°C (lead melts at only 300°C). At this temperature it is also the end product of oxidation of other lead oxides in air. This is often done with a set of bellows pumping air over molten lead and causing the oxidized product to slip or fall off the top into a receptacle, where it quickly solidifies in minute scales.
PbO –(293 °C)→ PbO –(351 °C)→ PbO –(375 °C)→ PbO –(605 °C)→ PbOUsage examples of "litharge".
Ores of Lead -- Geographical Distribution of the Lead Industry -- Chemical and Physical Properties of Lead -- Alloys of Lead -- Compounds of Lead -- Dressing of Lead Ores -- Smelting of Lead Ores -- Smelting in the Scotch or American Ore-hearth -- Smelting in the Shaft or Blast Furnace -- Condensation of Lead Fume -- Desilverisation, or the Separation of Silver from Argentiferous Lead -- Cupellation -- The Manufacture of Lead Pipes and Sheets -- Protoxide of Lead -- Litharge and Massicot -- Red Lead or Minium -- Lead Poisoning -- Lead Substitutes -- Zinc and its Compounds -- Pumice Stone -- Drying Oils and Siccatives -- Oil of Turpentine Resin -- Classification of Mineral Pigments -- Analysis of Raw and Finished Products -- Tables -- Index.
But in defining a reducing agent as one which removes oxygen, or sulphur, from a metallic compound so as to set the metal free, it must be remembered that sulphur itself will reduce metallic lead from fused litharge, and that oxygen will similarly set free the metal in fused lead sulphide.
For example: 3 grams of an ore containing a good deal of pyrites and a little galena, gave, when fused with litharge, 16.
If some particles of unburnt carbon remain in the bone ash, a similar result will be produced by the escape of bubbles of carbonic acid as soon as the fused litharge comes in contact with them.
Consequently, if the lead rests on a porous support, which allows the fused litharge to drain away as fast as it is formed, a fresh surface of the lead will be continually exposed to the action of the air, and the operation goes on until the whole of the lead has been removed.
Detach the slag, replace in the crucible, and, when fused, add a mixture of 20 grams of litharge and 1 gram of charcoal.
The reaction takes place without evolution of gas, and in its working the only point is to so regulate the heat that the litharge shall not fuse and drain under the unattacked quartz, leaving it as a pasty mass on the surface.
Take 80 grams of litharge and 20 grams of a mixture of borax and soda.
The results of two assays, after deducting for the silver in the litharge used, were 3.
There n'as quicksilver, litharge, nor brimstone, Boras, ceruse, nor oil of tartar none, Nor ointement that woulde cleanse or bite, That him might helpen of his whelkes* white, *pustules Nor of the knobbes* sitting on his cheeks.
There was no mercury, sulphur, or litharge, No borax, ceruse, tartar, could discharge, Nor ointment that could cleanse enough, or bite, To free him of his boils and pimples white, Nor of the bosses resting on his cheeks.
Gorgidas had dosed the cut with a murky brown fluid he called barbarum: a compound of powdered verdigris, litharge, alum, pitch, and resin mixed in equal parts of vinegar and oil.
I tried everything: blood, hair, the soul of Saturn, marcasites, aes ustum, saffron of Mars, tincture of iron, litharge, antimony.