Hi! This will be a tough ring to guess. Thick metal band rings are where you need the exact length. The reason is because the ring is so tall/thick.
I prefer it on the fourth finger as it's a bold look, and I like bold rings on the fourth finger.
To me, the fourth finger shows off bold rings the best while still keep the hands looking nice.
However, if your fingers are short on the lower half of the fourth finger (the bottom where rings land), the ring won't look good. It will make the finger look even shorter.
This photo below (from one of the photos you posted above) is what I mean. The ring in my opinion is too tall as it is almost to her knuckle. There needs to be a bit of skin showing below the knuckle to keep the finger looking thin. This person has thin fingers, yet because the ring is too tall for her finger, the ring just looks like a big fat Band-Aid to me.
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To give another an example of what I am talking about, here is a photo of a nice fit (photo is from Tiffany website). You can see there is skin showing below her knuckle. This person's fingers actually seem thicker than the above person's fingers. However, the ring is much more gorgeous on her because the lower half of her finger is probably longer, so she can wear a taller/thicker ring. Therefore, with the same ring, there is skin showing below her knuckle because her fingers are longer. The eye can still see the beautiful line of her finger. It looks like an artistic ring on her, not a wide Band-Aid.
If the fourth finger does not work, my second choice is on the middle finger, like the photo below. I am not a fan of big, bold silver rings on the index finger as I find that look a bit aggressive, moto-chic, which is not my aesthetic.
I hope that made sense. That's just my opinion of course. Jewelry style & fit is 100% preference, so it's what you love.
Hope that helps you decide! You could order two sizes to try it on your fingers and keep the size you like best. Tiffany online service is excellent.
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