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A multi-analytical approach for the study of brazilwood and its lake pigments was carried out based on historically accurate reconstructions. Recipes for brazilwood lakes from the fifteenth century technical textLivro de como se fazem as coresand the Winsor & Newton nineteenth century colourman's archive were reproduced and compared. Both primary sources allowed for the successful preparation of brazilwood lake pigments with colours that vary from light pink to dark red. The main steps and ingredients for the manufacture of these pigments were common in both sources, particularly the addition of Al3+in the form of alum, and calcium carbonate (chalk). Reconstructions revealed that the latter acts as a pH buffer and filler, controlling the pH at which the lake pigment precipitates. The main difference between the two sources is that the nineteenth century recipes give the quantities for all ingredients, the precise temperatures and time, and achieved higher relative pigment yields (75% versus 45%). Full chemical characterisation of the reconstructions provided detailed information on the individual steps in the pigment manufacture and revealed that the presence of calcium sulphate dihydrate (gypsum) in the final pigment was a result of its formationin situ. Infrared, reflectance, and fluorescence spectroscopy proved to be essential and complementary techniques: while infrared was used to characterise additives and binders, reflectance and fluorescence data were fundamental for identifying the chromophore. The pigments and paints produced can now be used as standards for the identification and investigation of brazilwood lake pigments found in artworks. [ABSTRACT FROM PUBLISHER]

Brazilin is a nearly colorless dye precursor obtained from the heartwood of several species of trees including brazilwood from Brazil, sappanwood from Asia and the Pacific islands, and to a minor extent from two other species in Central America, northern South America and the Caribbean islands. Its use as a dyeing agent and medicinal in Asia was recorded in the 2nd century BC, but was little known in Europe until the 12th century AD. Asian supplies were replaced in the 16th century AD after the Portuguese discovered vast quantities of trees in what is now Brazil. Overexploitation decimated the brazilwood population to the extent that it never fully recovered. Extensive environmental efforts currently are underway to re-create a viable, sustainable population. Brazilin is structurally similar to the better known hematoxylin, thus is readily oxidized to a colored dye, brazilein, which behaves like hematein. Attachment of the dye to fabric is by hydrogen bonding or in conjunction with certain metallic mordants by coordinative bonding. For histology, most staining procedures involve aluminum (brazalum) for staining nuclei. In addition to textile dyeing and histological staining, brazilin and brazilein have been and still are used extensively in Asian folk medicine to treat a wide variety of disorders. Recent pharmacological studies for the most part have established a scientific basis for these uses and in many cases have elucidated the biochemical pathways involved. The principal use of brazilwood today is for the manufacture of bows for violins and other stringed musical instruments. The dye and other physical properties of the wood combine to produce bows of unsurpassed tonal quality. [ABSTRACT FROM AUTHOR]

Aceria inusitata Britto and Navia n. sp. (Acari: Eriophyidae) is described from protogynes, deutogynes and two forms of males occurring under a 'patches of webbing' from 'pau-brasil,' Caesalpinia echinata L. (Caesalpiniaceae), leaves. This is the first example of a deuterogynous eriophyid mite in tropical regions with two forms of males, one resembling the protogyne and the other the deutogyne. In addition, biological observations are presented. Aberoptus cerostructor Flechtmann, is given a new generic assignment, Aceria cerostructor n. comb. [ABSTRACT FROM AUTHOR]