GOGO, ENTADA SCANDENS BENTHAM, AND ITS EFFECT ON 

 GOLD AND GOLD SOLUTIONS 



By F. T. Eddingfield 

 (From the Division of Mines, Bureau of Science, Manila, P. I.) 



Since in the Philippines go go juice has been universally used 

 by the natives in panning gold-bearing sands, an investigation 

 of its properties seemed desirable. The native has for panning 

 a large wooden bowl, batea, which is about 65 centimeters in 

 diameter, and slopes to a point in the center like a very flat 

 inverted cone. The panner, usually a woman, has a little gogo 

 bark at hand which at certain times she squeezes over the pan, 

 causing the juice to fall on the water in the pan. It is believed 

 that in this way more gold is recovered, by causing the fine gold 

 to settle quickly and not float away. 



According to Bacon, 1 gogo is taken from the plant Entada scan- 

 dens Bentham. It is called "gogo" by Tagalogs and "bayogo" 

 and "balogo" by the Visayans and Pampangans. The solution 

 obtained from gogo is neutral, neither acid nor alkaline. Its 

 chief constituent is saponin, a complex vegetable poison, which 

 has a very slight acid reaction, and constitutes one of the groups 

 of glucosides. These are generally colloids. Bacon further 

 states that saponin has the quality of holding bodies in suspen- 

 sion ; such as powdered charcoal, lead sulphide, barium sulphate, 

 and barium carbonate ; and that mercury is readily "killed" and 

 oils emulsified by its aqueous solutions. In the following pages 

 the aqueous solutions of gogo bark will be referred to as "gogo." 



Several tests were made with mercury, and it was noted that 

 when gogo was added the mercury was easily divided into minute 

 globules which refused to be reunited. This is caused by a thin 

 film being formed around each globule which "soils" it and makes 

 it difficult for fresh faces of mercury to come in contact with 

 each other. It also robs the mercury of its quality of amalga- 

 mation with gold, silver, and copper ; a condition which has prob- 

 ably given rise to the belief, held by some, that Paracale gold 

 will not amalgamate. 



^This Journal (1906), 1, 1022. 



135 



