![]() However, our findings show that Gilsonite, or North American Asphaltum, a natural, resinous hydrocarbon found in the Uintah Basin in northeastern Utah, is a very hard substance. According to sources, Dead Sea bitumen contains less soft hydrocarbons than typical bitumen sources, such as Trinidad. We have contacted some Jordanian mineral exporters, so we will see what they say in due time. Of course, the origin of the English word “mummy” is from the Persian or Arabic word “mumia” or “mumiya,” meaning asphaltum or bitumen, which may have caused some confusion about the real source of this pigment.įor further reading on this subject, I recommend the article by Sally Woodcock (1996), “Body Colour: the Misuse of Mummy,” The Conservator, 20.Īs an aside, Natural Pigments is trying to obtain Dead Sea or Palestinian bitumen. Perhaps this error resulted in some confusion, which may have lead individuals to grind actual mummies for use as a pigment, perhaps as an alternative to asphaltum. It was at one time believed that bitumen was used in the bandages of mummies, but this was generally not the case (instead, balsams were used). In another example, Zahira Veliz identifies this term in a collection of Spanish and Portuguese treatises of the sixteenth and seventeenth centuries: from a Portuguese manuscript of 1615, the use of bitumen is specified in a varnish for marquetry, which was part of a recipe to make a red lacquer with the pigment and rosin. Apparently, this was a typical name for such a binding agent mixture because it is found in another passage in the Neapeler Codex from the fourteenth century and by Valentin Boltz, writing on the same subject in Illuminierbuch (1549). In his essay about manuscript painting from 1988, Heinz Roosen-Runge mentions a recipe from a German manuscript of the late fifteenth century, in which bitumen is used to describe an aqueous binding agent for manuscript painting made of a mixture of fish glue and rabbit skin glue. This definition includes Gilsonite and glances pitch. ![]() ![]() Gilsonite ore-a type of asphaltum or bitumenĪsphaltum typically designates a species of bitumen, including dark-colored, comparatively hard, and non-volatile solids composed of hydrocarbons, substantially free from oxygenated bodies and crystallizable paraffin sometimes associated with mineral matter, the non-mineral constituents being difficultly fusible and mostly soluble in carbon disulfide the distillation residue yields considerable sulfonation residue. However, the term used in painting usually designated a substance based on hydrocarbons derived from petroleum (at least after the sixteenth century). The English term “bitumen” is used to designate a wide variety of hydrocarbon substances, just as pitch is a term used to designate bituminous substances based on petroleum (such as “glance pitch”) and substances from the sap of trees (such as “Burgundy pitch”). Depending upon its place of origin or technique of manufacturing, bitumen possesses a composition of different characteristics. Bitumen either occurs naturally or is obtained from the synthetic distillation of petroleum. From the viewpoint of current art historical research, bitumen represents a large group of organic substances, which consist of an indefinable mixture of high-molecular hydrocarbons. Asphaltum and bitumen are broad terms for many substances based on high-molecular hydrocarbons.
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