Good question. I also don't have a scale to see the difference. I have a minnow head mold that says the small one is a 1/48 with a barbed collar. My thought is that it might have been before they added the collar, but it's more like a 1/32 now. Suits me as that is about as small as I use anyway. I'm sure that the 1/16 is heavier than that, but it's not 1/8 for sure. I'm also interested to see the results of this if someone has a scale to tell the real truth.