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词汇 Gum copal
分类 英语词汇 英语翻译词典
释义

Gum copal

英语百科

Gum copal

The chemical structure of a gum copal molecule as represented by carbon chains and the other atoms found in the molecule.

Gum copal, also known as manila copal, is a resin produced by the sap of the forest tree (Daniellia sp.), due to common impurities and differences in regions, gum copal ranges in colors from blacks to yellows to whites. Gum copal, along with ivory and slaves, was a significant export from East Africa in the nineteenth century. Gum copal exists in a state very similar to that of amber but with some primary differences. It is commonly mistaken for amber and often times sold at gem shows or other areas as amber. Unlike amber, gum copal is usually only 100-1,000 years old and it has not yet fossilized. Gum copal usually sells for $750-$1500 USD per metric ton in rock form and $1500-$6500 USD Per metric ton in powder form.

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