SEXING SOCIETY FINCHES

Question
QUESTION: Hi,
 I recently acquired a 7 month old fawn colored society finch from a woman who didn't know the sex of it but what guessing male because it was chirping a lot. So, after about a month, I decided that "he" needed a companion. I went to the pet store where they had societies and spice finches in one cage. One of the societies had a ruffled tail and the other which I saw in and out of the nest seemed fine and so assuming it must be a female, I bought it because everyone kept telling me that 2 males will fight.
 When I put it in the cage with the other, the 1st finch seemed to be chasing it for a while and the newcomer even opened it's mouth a few times in a defensive way. Now, 2 days later, they are getting along great. They preen each other a lot. However, the 1st finch seems quiet compared to the newcomer with only quiet little chirps in comparison to the other finch which does a lot of really long singing, stretching out it's neck and fluffing it's feathers. I can't find anywhere anything that clear describes male and female behavior or any videos. So, I was wondering if there's any way to tell for sure or if you have any society finch videos that clearly show their behavior of each sex. Thanks
Irene

ANSWER: The only sure way to sex societies is to have them sexed. Whoever told you that two male Societies will fight lied . Societies are extremely social and having a pair of the same sex will be just as happy with eachother as a boy and girl pair

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QUESTION: Hi,
Thankyou so much for your answer. It puts my mind at ease. Just in case I had a pair, I had given them a nest and a small box of nesting material which have been in there for a couple of days. They have not seemed inclined to do anything with them. I saw one picking up a blade of grass for the other (I put a few blades in there) but still nothing. So, I am assuming that both are male. They really like to cuddle and preen each other and only the one does a lot of singing and the other does just little chirps. So, if they were both males, would the more dominant one be the only one singing or would they both be singers? Thanks
Irene

Answer
First off, what do you mean by grass? As in grass from your lawn or a pet store? Finches can be particular about their nesting material.
It really depends on the bird. Societies don't exist in the wild and never have so they really don't have any of the mating instincts that other finches do