Calculating statistical relevance

Hi all

I'm having a statistical issue. I have a 2 sided dataset, of which i am trying to compare isotopes of 2 different radioactive compounds on statistical significance (i want to look at every point and be able to say that either it is withing the margins or not). My question is, how do i do this for each point? (This is a picture of the points)

https://lh6.googleusercontent.com/-Q...ple+values.png

I have tried so far;

T-Test

ChiSquared

And just to try if it had any effect, normal distribution etc.

I'm using excel, and it has been a while for me since i have done any statistical math.

I hope anyone could help.