The reproduced scent of ambergris is predominantly a mix of labdanum and benzoin. The balsams have a sweet, aromatic, resinous scent with an odour resembling vanilla or benzoin. Tincture of benzoin is benzoin resin dissolved in alcohol. The kingdom was also rich in camphor, benzoin, gold, lignaloes, rattan, honey and slaves. It is possible that onycha was this mix of labdanum and Styrax benzoin. Unlike Siamese benzoin, Sumatran benzoin contains cinnamic acid in addition to benzoic acid. Stacte may have been light myrrh treated with benzoin. In 1833, Eilhard Mitscherlich produced it by distilling benzoic acid (from gum benzoin) and lime. A Roman supper sometimes included shellfish prepared with pepper, cinnamon, and benzoin root. There are two common kinds of benzoin, benzoin Siam and benzoin Sumatra. Proton transfer and elimination of the cyanide ion affords benzoin as the product. Scientists says "styrax benzoin" from Sumatra has the best quality. One popular route entails reduction of benzoin using zinc amalgam. However it seems that the root of benzoin was also used.