Bois durci

Bois durci is a mixture of blood, usually from cattle, soot, and fine hardwood sawdust. This compound has been molded into a wide variety of shapes,... 

The method was used to shape bois durci, an early, natural polymer, which was made into plaques and large items such as ink... 

Earlier chapters focused primarily on an analysis of today s dominant plastic materials, which for the most part, date back to the 20 century. Before that era, not only natural resins, such as beeswax, amber, copal resins, gutta-percha, shellac, bitumen, horn, tortoise shell, and materials derived from cellulose derivatives (cellulose nitrate and acetate), from blood protein (mostly as Bois Durci), or from casein are used to find a variety of applications. Our ancestors used these natural materials to produce, among other things, pieces of jewelry, decorative items, or articles of daily use such as tins, picture frames, or desktop utensils where these materials often replaced metals, wood, paper, or ceramics. 

In simmering water, dark-colored blood albumin masses (Bois Durci) release part of their hemoglobin, thus tinting the water dark. Another, more sophisticated test method identifies the iron contained in hemoglobin by adding ammonium thiocyanate. 

Figure 1.1 Bois durci mirror from France, circa 1880 (Kolsch Collection).

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