Litharge (Massicot) (100 g)

Product Details:

WARNING! Contains Lead. Read the MSDS for cautionary statements.
100 g jar (3.5 oz)
Rublev Litharge is made by a modern process of direct oxidation of lead, wielding a finely divided yellow orange powder of high purity. Litharge is monoxide of lead and usually contains about 93 percent of lead and 7 percent of oxygen. It is not used as a pigment in oil painting, but was used as a pigment in manuscript illumination (egg tempera and watercolor) and infrequently in fresco painting.

Pigment Names
Common Names:	English: litharge, yellow lead monoxide French: plomb oxidé jaune German: Lithargit Italian: Spanish: lithargita, plomo amarillo
Synonyms:	English: chrysitin, lead monoxide, lead ocher, masicotite, massicolite, massicottite, masticot, piombo ossidato, plumbic ochre French: plomb oxidé jaune German: Bleiglätte, Bleioxyd, Masicotit, Massicolit, Massicottit, Silberglätte Italian: Spanish: litarjirio nativo, masicotita, massicolita, massicottita

Origin and History
Both massicot and litharge often are terms used for the same pigment, but more correctly each are lead monoxides derived from different sources. Massicot is the unfused monoxide of lead made by the gentle roasting of white lead at 300° C. The heat causes the white lead to give off carbon monoxide and water, leaving a soft, sulfurous yellow powder that is massicot. Litharge is the fused and crystalline oxide, which is formed from the direct oxidation of molten metallic lead. Litharge is more orange in comparison to massicot due to the content of some red lead (lead tetraoxide). Litharge is rarely seen used as a pigment in comparison to massicot but was more commonly employed in varnishes and glazes. The manufacture of yellow lead monoxide has been known since Ancient times and found in Egypt, Italy, Germany, across Europe in general and in the North and South Americas.

The name massicot is derived from early Arabic, through Spanish mazacote and the French name for oxide of lead.

Source
Lead monoxide exists in two modifications, litharge and massicot. Litharge, or alpha lead monoxide, is a red or reddish yellow solid, has a tetragonal crystal structure, and is the stable form at temperatures below 488° C (910° F). Massicot, or beta lead monoxide, is a yellow solid and has an orthorhombic crystal structure; it is the stable form above 488° C. Massicot is the orthorhombic variety of PbO. The tetragonal variety is the mineral litharge. Both minerals have the same chemistry, PbO, but different structures. Because of this they are called dimorphs ("di" means two and "morph" means shape). Two other much more famous dimorphs are diamond and graphite; both of which are composed of carbon. Litharge is similar to the more common massicot, but the tetragonal structure is apparently lighter than massicot's orthorhombic structure. Litharge is also more orange in color. The two minerals are easily distinguished in petrographic microscopes due to optical differences. It has been found that many crystals of massicot have a fringe of litharge.

Litharge, which is produced by air oxidation of lead, is the most important commercial compound of lead; it is used in large amounts directly and as the starting material for the preparation of other lead compounds. Containing roughly 93 percent lead and 7 percent oxygen by weight, it is manufactured by the oxidation of metallic lead in a variety of processes, each resulting in a distinctive variation in physical properties. Hence, it is available in many particle sizes and in two crystal forms.

Permanence and Compatibility
The color appears to be permanent in all mediums, but due to its siccative effect on oil it cannot be used as a pigment in this vehicle. Litharge is an effective drier in linseed, poppy seed, walnut and safflower oil.

Use in Oil Mediums and Varnishes
The following are directions from Mackenzie's Five Thousand Receipts by Colin MacKenzie:

"When painters wish to obtain a common colour of the ochrey kind, and have no boiled oil with them, they may paint with linseed oil, not freed from its greasy particles, by mixing with the colour about two or three parts of litharge, ground on piece of porphyry with water, dried, and reduced to fine powder, for 16 parts of oil. The colour has a great deal of body, and dries as speedily as if mixed with drying oil."

How to Make Drying Oil
The following are directions from Mackenzie's Five Thousand Receipts by Colin MacKenzie:

"Boil together for two hours on a slow and equal fire, half an ounce of litharge, as much calcined ceruse [Note: Substitute calcined ceruse with litharge], and the same of terre d’ombre [Note: umber] and talc [Note: hydrated magnesium silicate], with one pound of linseed oil, carefully stirring the whole time. It must be carefully skimmed and clarified. The older it grows the better it is. A quarter of a pint of this dryer is required to every pound of colour."

Italian Medium
Another source describes the following recipe as a method of preparing a drying oil painting medium with litharge and wax, essentially making a "black oil." This medium was first described by Jacques Maroger on page 164 of his book, Secret Formulas and Techniques of the Masters. It is made in the following way (all measurements are given by weight):
Raw linseed oil ....................... 10 parts
Litharge ........................................ 1 part
Beeswax ....................................... 1 part
It is advisable to grind the litharge with a little of the oil before mixing it with the rest of the oil. The mixture is then simply heated to 250° C. and when it turns black the product is finished. In cooling it thickens into a paste.

In actual usage, the results are very close to the true Italian medium. This paste has the advantage that it can be made by anybody, without difficulty. It is mixed (by means of the palette knife) into each of the colors on the palette, including the white. There can be no definite prescription for its use, as it is a matter of individual taste; also the use may vary with different subjects. It can be thinned with raw oil or, preferably, with essence of turpentine. This can be worked into it with the palette knife for use on the palette, or else kept in the oil cup for further dilution of the colors.

Oil Absorption and Grinding
Litharge is not used as a pigment in oil painting, because of its siccative effect on oil. It can be used with aqueous media such as egg tempera, gum Arabic (watercolor) and animal glue. It can also be used in encaustic (wax) technique and in true fresco technique.

Toxicity
Litharge is toxic if inhaled as a dust or if ingested. Using the pigment to make paint or drying oil can be hazardous, so protective clothing and work hygiene must be used to ensure safe use. The sale of lead compounds in some countries has been prohibited. Painters may suffer from "painters' colic" or "plumbism" if they are careless in using it. Care should be used in handling the dry powder pigment so as not to inhale the dust. Do not smoke, eat or drink while using the pigment in any form, including in a paint binder.

Pigment: Litharge (Massicot)

Pigment Information
Color:	Yellow
Colour Index:	Pigment Yellow 46 (77577)
Chemical Name:	Lead Monoxide
Chemical Name:	PbO
ASTM Lightfastness Rating
Acrylic:	Not Rated
Oil:	Not Rated
Watercolor:	Not Rated
Properties
Specific Gravity:	9.14–9.35
Density:	9.56 g/cm³
Hardness (Mohs):	2
Refractive Index:	n_α=2.510 n_β=2.610 n_γ=2.710