272214
In an experiment described by Tyndall , one of the cube 's vertical sides is coated with a layer of gold , another with a layer of silver , a third with a layer of copper , while the fourth side is coated with a varnish of isinglass .
 None
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
 Entities:  
Answer:
 None