Speech is silver 
And silence, they say, is gold. 
But when bitter words remain 
Unuttered  
Till they are forgotten,  
Duels and wars remain 
Unfought 
Till the reason is forgotten,  
And peace remains 
Untouched  
Till the humans evolve,  
Silence seems 
To be more precious than even diamond.
Jasbir Chatterjee
http://www.poemhunter.com/poem/silence-24/