How big is 8mm? How about 6mm? Here is a great way to see how wide a ring really is. Grab a few of nickels and stack them up, then follow the chart below:
Now you've seen how thick the rings are. In general, 6 to 8mm is mostly purchased by/for women. Over 8mm is mostly purchased by/for men. That's just how the typical purchaser chooses, but it's not a rule. If you're a woman that likes a chunkier ring, and it's available, go for it! Sometimes you want it a bit bigger so you can see the beautiful laser patterns even better.