Hey Epavlidi
No worries, at least you've come out and admitted you were wrong, takes a man to do that (apoligies if you're a woman)
1 gram = .03527396 ounces
31.1 grams = 1.097020156 ounces
So it's over by almost 10%
I got it from here http://www.myjewelrysource.com/misc/grams_to_ounce.htm
Either way, we know we are onto something special