Vegetable ivory

Mannans (Tagut Nut, Corajo, Vegetable Ivory, Carobean), (CgHioOg, mw 162.14. Poly-, meric polysaccharides which yield mannose on hydrolysis. They can be acetylated and nitrated... 

Ivory Nut (Corajo, Coroso or Vegetable Ivory). A hard white substance obtained from the tagud nut, such as Phytelephas Macrocarpa or negrito palm, which grows in Ecuador... 

F.01sen, USP 1510555(1924) CA 18,3722 (1924) [NH4C104 0-40, TNT 0-50, smokeless proplnt 15-50, combustible non-expl material(such as woodmeal or "vegetable ivory ) 3-10, paraffin 0-30, KN03 0.30 MnOz 0-30ps]... 

Mannans and glucomannans from plant sources all contain linear chains of (1 —> 4)-linked d-D-mannose and /J-D-glucose residues as their main structural features. The only true mannans (that is, polysaccharides containing 95% or more of D-mannose residues) so far examined from land plants are those from vegetable ivory (Phytelephas macrocarpa).90 96 The... 

The quest for imitations of ivory have led to the use of vegetable ivory, the hard white nuts produced by various tropical trees. The most common of these are the doum palm (Hyphanae thebaica) and the tagua Phytelephas macro-carpa). These nuts have a brown fibrous rind, but the meat inside is homogeneous white or yellowish white. Softer than ivory, these nuts are easy to carve, and are popular for making small items such as netsuke, buttons, beads, and jewelry. 

F ure 12.7 Vegetable ivory kernels natural, polished and broken. 

Figure 12.9 Vegetable ivory caivii sewing needle case, h o, and buttons.

In the unlikely event that it is impossible to determine whether an item is vegetable ivory, a drop of sulphuric acid will cause a pink spot to appear on cellulose after some minutes. However, this is irreversible and the spot cannot be polished away as the acid seeps into the material. It is therefore a destructive test, and not recommended. 

Vegetable ivory can be carved, turned or engraved, and it stains very readily. Due to its small size its uses have been limited, though several... 

In the latter half of the nineteenth century a whole industry grew up around the manufacture of vegetable ivory buttons. Some were intricately carved and multicoloured (Fig. 12.9), while others were completely plain. With the advent of early plastics, this industty faded. There was a lot of wastage in the production of buttons, and it is said... 

In the absence of animal ivory, vegetable ivory is again popular for small carvings, many of which reflect the shape of the nut (Fig. 12.9). The outer, brown husk is sometimes left for added effea. Today there is a large production of vegetable ivory netsuke in the Far East and the nut is also used for scrimshaw. A small amount of buttons is still produced. 

Schabilion, Shirl (1989). AU in a Nutshell. The Story of the Vegetable Ivory Nut. The Mississippi Petrified Forest. 

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