Dye Easter Eggs with a Man's Tie

I have never done this before but wanted to give it a try so I headed out to the thrift store and picked 3 ties to make Easter Eggs. Here is one link to show you how to do it:
http://www.consumerqueen.com/frugal-tips/diy-dye-easter-eggs-with-a-mens-tie#axzz1quXaxYgJ

Apparently they must be silk and I am not sure if these are!!! Also, dyed easter eggs should not be eaten if the have been left out of the fridge for more than 2 hours.